Method for producing homogenous fine-grain titanium material (variants)

FIELD: metallurgy, possibly production of homogenous fine-grain titanium material.

SUBSTANCE: according to first variant of invention method comprises steps of first heat treatment of blank of titanium material due to heating it till β-region; quickly cooling blank till (α + β)-region and forging it while creating at deforming process super-plasticity condition; then performing second heat treatment due to realizing recrystallization annealing for producing grain size in range approximately from 5 micrometers till 20 micrometers. According to second variant of method blank of double-phase titanium material is subjected to first heat treatment due to heating it till β-region. Heating temperature is in range approximately from 600°C till approximately temperature of polymorphous phase conversion of titanium material. Blank is quickly cooled till (α + β)-region and it is subjected to forging while creating super-plasticity condition. Then second heat treatment is realized due to performing recrystallization annealing. In the result double-phase material with grain size 15 - 20 micrometers is produced.

EFFECT: possibility for producing material that may be subjected to ultrasound flaw detection at high accuracy.

14 cl, 8 dwg, 3 tbl, 5 ex

 

BACKGROUND of INVENTION

The invention relates to a method of production of a titanium material. In particular, the invention relates to a method of production of a titanium material, which may be made of titanium materials for ultrasonic flaw detection, including methods and systems for ultrasonic inspection.

Production of titanium material with grain size and nature of the colonies particles having αTi-the structure may include important variables that affect the scope of titanium material. In addition, the grain size of the titanium and the nature of the colonies particle patterns αTi can affect ultrasonic interference and ultrasonic flaw detection in single-phase and two-phase titanium alloys and materials that can be used in ultrasonic inspection to determine the suitability of a titanium material for various applications. The grain size of titanium and character patterns colonies particles αTi may affect the methods of ultrasonic inspection and the results of such monitoring, if you create unwanted noise in ultrasonic flaw detection. This noise can hide or mask the fatal flaws of titanium, which may limit the scope of this Titan.

Patterns of colonies formed in the process of production of titanium mA is Arial, for example, during cooling, the titanium material having a high temperature. It is believed that colonies are formed when βTi is converted to αTi and can determine the "textured" microstructure of titanium material. Between grain αTi and the main grain βTi there is a certain crystallographic relationship, in which there are only three crystallographic orientation in which αTi will be formed from this grain βTi. If the cooling rate is large enough and there is a uniform nucleation αTi across the grain, neighboring particles αTi have different orientations, and each behaves as various acoustic scattering object. However, if there are only a few sites of nucleation αTi in the grain βTi, particles αTi in this area will grow with the same orientation, resulting in a structure of the colony. This colony is an acoustic object. Because the colony is formed in the grain βTi, the size of the colony is smaller than the grain size αTi. Although thermo-mechanical effect, which is based on dynamic recrystallization in the temperature range α+β to achieve a uniform fine grains (RMZ) particles α Ti and prevents the formation of colonies with improved microstructure t is Tana, in the titanium material can be certain defects. These defects can be very undesirable for some applications of titanium material. Thus, the defects should be detected prior to the use of titanium material in a variety of applications that are sensitive to the microstructure.

Methods of production of titanium material are known and can be different. One such method of production of a titanium material is based on the dynamic recrystallization of titanium material in the temperature range α+β. This recrystallization is designed to achieve a relatively uniform fine grain (RMZ) αTi particles and prevents the formation of colonies. Although this type of recrystallization is designed to improve the microstructures of titanium material, in-process titanium material can occur defects that limit the scope of the titanium material. Some of the defects in the titanium material is difficult to detect using conventional methods of ultrasonic flaw detection.

Non-destructive testing of components and structures by ultrasonic testing is widely used in the art for testing and evaluation of such products.

Ultrasonic inspection and tests, as a rule, require that defects or n is abundance in products and structures would demonstrate different acoustic behavior compared with solid products and designs, subjected to ultrasonic processing to detect these defects. The different behavior allows the ultrasonic inspection to detect defects, grain, disturbance patterns, and other relevant microstructural characteristics (defects) of the material. Materials, which are used to produce products and structures with large elastic anisotropic grain type steel castings, titanium alloys, and Nickel alloys are often very difficult to verify by the method of ultrasonic flaw detection. Difficulties arise, at least partly because the sound waves that are used for ultrasonic flaw detection, reflected from grain and from arrays of grains, dividing the total elastic behavior, and create a background "noise". Created interference may mask the defects of material and are, therefore, highly undesirable.

In the ultrasonic flaw detection methods are focused ultrasonic beams, which increases the fraction of defect in any instantly dubbed the volume of material in designs and products. An improved method of ultrasonic flaw detection can identify the signs are based on the maximum signal, as well as on the signal noise. The scattering of sound in a polycrystalline metal body, which is also formulated in this field of technology is key as the weakening of the propagating sound waves, can be described as a function, at least one of grain size corresponding to the characteristics of the material and the frequency of the ultrasound. As a rule, describes three different functional relations for scattering, frequency and grain size, namely:

for λ>2πD·and approximately Tν4Θcalled "Rayleigh scattering";

for λ>2πD·or λ≅D·a, equal to about Dv2Σcalled "stochastic" or "phase" scattering;

for λ<<D·a ∝ 1/D, called "diffusion" scattering;

where a is the attenuation, λ is the wavelength of the ultrasonic energy, ν - frequency ultrasonic energy, D is the average grain diameter, T is the volume scattering grain and Θ and Σ scattering factors, based on the elastic properties of the scanned material.

The microstructure of the titanium material can be determined by measuring the scattering of sound in the material. Sensitivity to scattering of sound microstructure of the titanium material can be attributed to particles αTi, which are collected in the colony. Typically, these colonies titanium material have a common crystallographic (and elastic) orientation, and these colonies particles αTi can behave like large grains in the titanium material. Individual particle αTi may have a diameter of 5 μm, is, however, a colony of particles α Ti may have a size greater than 200 μm in diameter. Thus, the contribution of size due to the sensitivity to scattering of sound from particle αTi may vary, for example, to change more than 40 times among the different microstructures. In addition, the sensitivity to scattering of sound from particle αTi may vary in the range from randomly crystallographically oriented particles αTi to particles αTi in crystallographically oriented colonies particles αTi.

Although ultrasonic inspection of most products of the titanium material can be made with some degree of reliability, shape, size, configuration, structure and orientation of products, grains of titanium material and microstructure formed during the production of titanium material subjected to ultrasound treatment, can introduce errors in the results of ultrasonic testing. Thus, in order to be acceptable titanium material for some applications, it is desirable to provide methods for the production of titanium material, which ensure the production of products and structures made of titanium, which can be subjected to ultrasonic flaw detection. The latter improves the definition and differentiation of interference in the process of ultrasonic flaw detection. Thus, the method of ultrasonic flaw is the request may determine, whether the noise in ultrasonic flaw detection result of the defect in the titanium material or arose due to other factors.

Therefore, there is a need in the production method of a titanium material, which is appropriate for producing a titanium material, components and structures that may be subjected to ultrasonic flaw detection with improved properties for the determination and separation of interference in the process of ultrasonic flaw detection.

BRIEF description of the INVENTION

The present invention provides a method of production of a homogeneous fine-grained titanium material in which the titanium material has a grain size in the range from approximately 5 μm to about 20 μm the Method includes the stage of preparing a billet of titanium material; conducting a first heat treatment of the workpiece of titanium material for heating the block to β-scope; rapid cooling of the billet titanium material from β-up to α+β-scope; forging billet of titanium material and the second processing billets of titanium material. The production method of a titanium material includes processing the workpiece titanium material under superplastic conditions during the production of titanium material.

This izobreteny which also includes the method for the production of homogeneous fine-grained titanium material, in which the titanium material has a grain size in the range from about 15 microns to about 20 microns, providing mainly equiaxial grain titanium and mostly grain titanium one size and largely uniform distribution of the particles of the second phase and alloying elements. The method includes the following stages: preparation of the billet titanium material, obtaining a titanium material including two-phase titanium material; conducting a first heat treatment of the workpiece of titanium material to heat the billet of titanium material to β-scope; rapid cooling of the billet titanium material from β-up to α+β-scope; forging billet of titanium material and the second thermal processing of the workpiece of titanium material. The production method of a titanium material includes processing the workpiece titanium material under superplastic conditions in the implementation of this method of production of a titanium material. The production method of a titanium material includes heating a billet of titanium material to a temperature in the range from approximately 600°With up to approximately Tpt, where Tpt is the temperature of the polymorphic phase transformation of titanium material.

These and other aspects, advantages and salient features of the invention the article is chickpeas apparent from the following detailed description with reference to the attached drawings, on which the same parts are denoted by the same digital items and disclose variants of the invention.

BRIEF DESCRIPTION of DRAWINGS

The figure 1 shows a micrograph of the material T under the following conditions: (a) conventional procurement; (b) conventional forged; (C) a workpiece with a uniform fine grain (RMZ); (d) forging of billets RMZ.

The figure 2 presents icosahedral image obtained from analysis of a sample of material T using the analysis of the backscattered electrons (EBSP) under the following conditions: (a) conventional procurement; (b) conventional forging.

(C) procurement REP; (d) forging of billets REP;

The figure 3 shows the pole figures [0001]obtained using EWZR-analysis of Ti6242 under the following conditions:

(a) conventional procurement; (b) conventional forged; (C) procurement REP;

(d) forging of billets RMZ.

The figure 4 shows the image blocks Ti6242 when scanning with a frequency of 5 MHz, and the blocks contain many blind holes with a diameter of 0.79 mm, which are drilled to a depth of 25 mm below the top surface of the block. This drawing on the left above shows the titanium billet RMZ, top right is the usual titanium billet, bottom left - forged from conventional titanium and the bottom right is forged from titanium RMZ, where C - scan images are made with a frequency of 5 MHz and a weakening of the mind by 12 dB.

The figure 5 shows the image blocks Ti6242, scanned with a frequency of 5 MHz, and the blocks contain many blind holes with a diameter of 0.79 mm, which are drilled to a depth of 25 mm below the top surface of the block. This drawing on the left above shows the titanium billet RMZ, top right is the usual titanium billet, bottom left - forged from conventional titanium and the bottom right is forged from titanium RMZ, where C-scan images are made with a frequency of 5 MHz and the attenuation of the noise 34 dB.

The figure 6 presents a graph of the average of the signals from the blind holes towards those that are mechanically executed in the unit of a conventional procurement.

Figure 7 shows a graph of the average noise blocks that are machined from conventional procurement.

The figure 8 presents a graph of the signal-to-noise blocks Ti6242 as a function of frequency.

Description of the INVENTION

The production method of the titanium material in accordance with the invention involves many stages of metallurgical processing used to obtain the titanium material with a homogeneous microstructure with small grain. The obtained titanium material suitable for various sensitive to the microstructure of applications, including, but not limited to, the manufacture of nodes turbines. The obtained titanium material may also be the difficulty validated methods and systems for ultrasonic testing. Ultrasonic inspection of titanium material, which is obtained by the production method of the titanium material in accordance with the invention, allows you to quickly determine the characteristics of a titanium material, for example, not limited to the above, the type of scattering, grain size and other characteristics of the microstructure.

The production method of the titanium material in accordance with the present invention includes at least a step for billet titanium material, in which the billet titanium material can be formed by any suitable method of production of a titanium material, including, but not limited to, the methods of powder metallurgy; the first heat treatment of the workpiece by heating to β-areas for titanium; rapid cooling of the heated billet of titanium material; forging cooled billet titanium material creation in the process of deformation of the titanium workpiece material conditions of superplasticity and the second heat treatment forged billet titanium material by recrystallization annealing. The final titanium material has a microstructure with a grain size in the range from approximately 5 μm to approximately 20 μm, for example in the range from about 15 microns to about 20 microns.

Ravnomerno what I microstructure of fine-grained titanium material is created by recrystallization of titanium material in the process of implementation of the method of production of a titanium material in accordance with the present invention. Recrystallization of titanium material often occurs during plastic deformation of titanium material, for example, during annealing or deformation of the titanium material. Consequently, the resulting microstructure grain size is in the range from approximately 5 μm to approximately 20 μm, for example in the range from approximately 15 μm to approximately 20 μm. Such a grain size of titanium material leads to the reduction of defects in the titanium material.

Normal processes of plastic deformation of titanium material is not able to form a highly homogeneous microstructure of titanium material. These known processes of plastic deformation can lead to the formation of various metallographic and crystallographic microstructures of titanium with various uneven distribution of the particles of the second phase and various forms of particles in the microstructure of the titanium material. Such microstructure of titanium material, even though it may have small grain sizes, creates significant levels of noise in ultrasonic flaw detection, which, of course, is undesirable.

Homogeneous microstructure with small grain size in the range from approximately 5 μm to approximately 20 μm, for example in the range from about 15 μm to about 20 MK is, can be formed by the method of production of a titanium material in accordance with the present invention. This homogeneous microstructure with small grain is formed by dynamic recrystallization grain titanium material, which is often accompanied by the creation of a second phase. Temperature and speed conditions of the production method of the titanium material in accordance with the present invention include a temperature range from approximately 600°With up to approximately TPPwhere TPPis the temperature of polymorphic transformation of titanium material. The velocity range for the method of production of a titanium material is in the range of approximately 10-5to about 10-1with-1. In the production method of the titanium material in accordance with the present invention a lower heat distortion temperature and higher strain rates provide a small grain size. These ranges of temperatures and strain rates include conditions superplastic deformation that end dynamic recrystallization of titanium material and the formation of recrystallized grains of the titanium material with a grain size in the range from approximately 5 μm to approximately 20 μm.

Conditions superplastic deformation created during the ne of the processing stages in the production method of the titanium material in accordance with the present invention. The microstructure of the titanium material may be homogeneous, if the titanium material is subjected to superplastic deformation, in which uniformity is ensured mainly by the receipt of equiaxial grains, and individual grains are basically the same size. In addition, any secondary phase particles of titanium material can be mostly evenly distributed in the titanium material, and any alloying elements in it can be mainly distributed between the phases. In General, a titanium material, which is obtained by the production method of the titanium material in accordance with the present invention provides, generally, unstructured condition, meaning that the titanium material does not contain colonies, which would prevent ultrasonic flaw detection. As a result, the noise in ultrasonic flaw detection can be reduced and the sensitivity of ultrasonic testing for the detection of defects in the titanium material is increased.

Billet titanium material, which is obtained by the production method of the titanium material in accordance with the present invention, may include a two-phase titanium material, for example a two-phase titanium alloy, which can be obtained using any suitable metallurgical process, including, but not limited to the United ASI, powder metallurgy. Titanium alloy may include any suitable titanium material or a titanium alloy, such as Ti64 alloys, alloys C, alloys TI-5Al-2.5Sn, alloys TI-5Al-2.5Sn-Eli, titanium alloys IMI550, titanium alloy VT8-1, titanium alloys VT6 and other titanium materials. Discussed here are the alloys are exemplary titanium materials for titanium products and designs in accordance with the invention. Description of the specific titanium alloys in no way limits the invention.

The formation of a homogeneous microstructure with fine grain titanium materials can be attributed to the initial microstructure of the titanium material before any deformation. For example, the initial microstructure of the titanium material before deformation in α+β-the area has a tendency to include grain, which is rough and plate. This grain size is in the range of from about 300 microns to about 500 microns.

Titanium material with a smaller and more uniform grain size, which can be obtained when the strain in the β-region can also be obtained by deformation in (α+β). In order to obtain the microstructure of the titanium material, there are several stages of forging according to the production method of a titanium material with a temperature of about the PP. Thus, recrystallization annealing or secondary deformation in the method of production of a titanium material are carried out in β-region to form a homogeneous microstructure with fine β-grain.

Different grain orientation initial titanium material in the presence of mechanical stresses in the implementation of the method of production of a titanium material can lead to uneven recrystallization. This uneven or non-uniform recrystallization (textured microstructure) can lead to uneven distribution of strain in the titanium material. The production method of the titanium material in accordance with the present invention can improve the uniformity of the strain distribution and the homogeneity of the microstructure of titanium material and, thus, will provide the desired microstructure of the titanium material.

The production method of the titanium material in accordance with the present invention will be discussed further in the examples for titanium materials. These examples are just examples of implementation methods of producing titanium material according to the present invention and do not constitute any limitation of the invention. In the scope of the invention also includes other methods of production of a titanium material. Additionally, values,ranges, and number, specified in the description are approximate, unless otherwise specified.

EXAMPLE 1

Prepared billet titanium material including two-phase titanium alloy (Ti-6242) with temperature TPPorder 1000°C. Billet titanium material were cut from the deformed β-the area of the rod of titanium material. The size of the blanks of titanium material was 100×100×200 mm Size βthe grain was of the order of 3-5 mm, the microstructure of the titanium material was extended or elongated in the direction of the deformation.

Billet titanium material was first heated to a temperature of β-field (T is approximately 1020°S, the exposure time is approximately 1 hour). Billet titanium material is then subjected to rapid cooling from the temperature β-area to create a uniform microstructure fine grains in α-β-region. Was formed dispersed lamellar microstructure, and a layer of titanium αphase were placed around the borders β-grain with a reduced thickness compared to conventional methods of production of titanium material. This method of production of a titanium material increases the grain and uniformity of the microstructure during recrystallization.

Forging in (α-β)-the field was carried out at a temperature T equal to approximately 875&x000B0; With, and with an average speed of warp 3×10-3with-1. This purpose was used isothermal hydraulic press with a capacity of 1600 tons, and the press included isothermal matrix node. Matrix node was made of heat-resistant Nickel alloy and is heated to the same temperature as the workpiece. Deformation of the titanium material production method of the titanium material in accordance with the invention was carried out by forging with changing axes of deformation. After having been successively carried out two stages of deformation (as described above), was formed homogeneous microstructure of titanium material with a grain size of approximately 5 microns. Deformation during each forging was 50% in relation to the size of the height of the workpiece of titanium material. The total relative deformation, as measured by the change in the square billet titanium material at each stage, was equal to 12. Accordingly, the titanium material was identified as being in a state of superplasticity, because the resulting grain size was approximately 5 μm, the heat distortion temperature was approximately 875°C, the speed of deformation ε was equal to approximately 3×10-3with-1and the sensitivity coefficient of velocity m was priblisitelno. To complete the recrystallization of titanium, billet titanium material were subjected to annealing at a temperature of deformation within approximately 1 hour.

EXAMPLE 2

Were prepared billet titanium material, consisting of two-phase titanium alloy (IMI550). The alloy had a temperature Tpt order 965°for ingot and Tpt about 980°for forging. Titanium material is formed ingot billet with an approximate size of 634×540 mm, was prepared according to the method of production of a titanium material, which included forging titanium material β-region. This stage was accompanied by a heat treatment at a temperature of about 1200°forging and pressing. This stage consisted of pressing, forging the square and profiling. Stage heat treatment was accompanied by heated to 1140°and wrought up to 390 mm These stages was accompanied by cooling. Next, the production method of the titanium material in accordance with the present invention included under heating to a temperature TPP-30°and forging up to 310 mm, heated to 1060°, forging up to 280 mm and air cooling. In addition, the billet of titanium material was subjected to temperatures of TPP-30°and forging, which included stage of hardening, forging the square and p is atilirovanie and forging up to 245 mm After heating the billet titanium material β-region, for example, at TPP+20°formed a homogeneous microstructure of titanium with a grain size in the range from about 700 microns to about 940 μm. Hardening of workpieces titanium material was carried out by cooling in water.

The production method of the titanium material in accordance with the present invention includes forging in (α+β)-region for titanium at a temperature of about 930°With an average speed of warp 10-1with-1. The dimensions of the billet titanium material were selected 230×435 mm For forging was used isothermal hydraulic press with a compression force of 1600 tons. The press was kept isothermal matrix node that was made of heat-resistant Nickel alloy and is heated to the same temperature as the workpiece of titanium material. The deformation corresponds to the forging with the same axes of deformation. After two repeated stages of deformation, as described above, was formed highly homogeneous microstructure of titanium material having a grain size in the range from approximately 4 to 8 mμ. Deformation during forging was approximately 50% relative to the measured height of the billet titanium material. The total relative deformation measured and the use of square billets of titanium material at each stage, was about 12.

Billet titanium material in the process of implementing the claimed method of production of a titanium material was in a state of superplasticity, because the grain size in the range from about 4 μm to about 8 μm, the heat distortion temperature of about 930°C, the strain-rate was equal to 10-3with-1and the coefficient of velocity sensitivity m is approximately 0.49. Billet titanium material were subjected to annealing at a temperature of deformation within about one hour for crystallization. The final dimensions of the plate were approximately 250×300 mm

EXAMPLE 3

Were prepared billet titanium material containing a two-phase titanium alloy (VT8-1), while billet titanium material had a temperature TPPabout 965°and in the forging of the ingot had a temperature TPPorder 1000°C. the Ingot, which had a size of approximately 628×535 mm, was subjected to forging β-area titanium. The forging was subjected to a heat treatment at a temperature of 1200°; included forging extrusion, upsetting, alignment, and profile. This stage was accompanied by a heat treatment at a temperature of about 1140°, hammering to approximately 390 mm and cooling. In addition, heat treatment approximately at TPP - 30°, forging up to 310 mm, heated to approximately 1060°and forging up to 280 mm was accompanied by cooling billets of titanium material.

Billet titanium material may be subjected to heating at TPP- 30°and forging. Forging involves upsetting, forging square, profiled and forging up to 245 mm After heat treatment in a β-region (TPP+20° (C) is formed of a homogeneous microstructure of titanium material with a grain size in microns. Cooling of the billets of titanium material was carried out in the water.

Forging in (α+β)-region for titanium material was carried out at a temperature of about 930°and the average strain rate of 10-3with-1. Billet titanium material had a size of 230×435 mm was used For forging isothermal hydraulic press with a capacity of 1600 tons. The press was kept isothermal matrix node that was made of heat-resistant Nickel alloy. Matrix node was heated to the same temperature as the workpiece of titanium material. Deformation corresponded to the axis of deformation of the forging. After the implementation of the two stages of deformation was obtained highly homogeneous microstructure of titanium material with small grain size of approximately 5 μm to approximately 8 μm. Deformation during forging was 50% relative to the part of the measured height of the workpiece of titanium material. The total relative deformation, as measured by the change in the square billet titanium material was equal to 12.

Titanium material in the process of implementation of the method of production of a titanium material has been in the area of superplastic because of the grain size in the range from about 4 μm to about 8 μm, the heat distortion temperature was 930°C, the speed of deformation ε was equal to approximately 10-3with-1and the coefficient m of sensitivity to strain rate was approximately 0.49. Billet titanium material were subjected to annealing at a temperature of deformation within approximately one hour for crystallization. The final size of the workpiece was 250×300 mm

EXAMPLE 4

Billet titanium material consisted of two-phase titanium alloy VT6, in which a billet of titanium material had TPPabout 990°when casting and TPPabout 990°when crafting. The ingot of the titanium material with size of about 736×1523 mm was subjected to forging β-region. Forging included heating to 1200°With elongation up to 620 mm and heating to 1200°C, followed by elongation to 510 mm Billet titanium material was then cut into two parts and subjected to further heat treatment. Heat treatment consisted of heating to 100° With extension up to 410 mm and air cooling. In addition, the proposed method of production of a titanium material consisted of heating at a temperature TPP-40°C, elongation up to 370 mm, heated to 950°and forging up to 320 mm, This method of production of a titanium material also included heated to 1060°With elongation up to 295 mm and the cooling water, after which the blank is cut into two parts. Then the billet titanium material was heated to Tpt -30°With, is deformed in the height of 390 mm, was heated to 960°, deformed height of 350 mm, was forged to the square of 280 mm and is profiled to 320 mm have been made since the repetition of these operations, and the final billet titanium material had a size of about 245 mm

Forging in (α+β)-the field was carried out at a temperature of about 940°and the average strain rate of 10-3with-1. The workpiece size was 230×435 mm was Used isothermal hydraulic press with a capacity of 1600 tons. The press was kept isothermal matrix node that was made of heat-resistant Nickel alloy and is heated to a temperature of billet titanium material. Deformation corresponded to the axes of deformation. After you have completed two stages of deformation, was formed titanium material with highly homogeneous microstructure with the grain size is in the range from about 6 mμ to about 10 microns. Deformation during forging was approximately 50% with respect to the size of the billet titanium material. The total relative deformation, as measured by the change in the billet of titanium material, was about 12.

When the grain size in the range of 6 μm to about 10 μm, the heat distortion temperature of about 930°C, strain rate of approximately 10-3with-1and the coefficient of sensitivity to deformation of the order of 0.35 was found that in the production method of the titanium material in accordance with the present invention have been achieved conditions of superplasticity. To achieve recrystallization billet titanium material were subjected to annealing at a temperature within approximately one hour. End billet titanium material had a size of 250×300 mm

EXAMPLE 5

Used billet titanium material, consisting of two-phase titanium alloy (VT6), in which the titanium material has a temperature TPPabout 990°ingot and TPPabout 990°in the form of forgings. The dimensions of the ingot were about 736×2500 mm Billet titanium material were cut into pieces the size of 180×220 mm, the grain Size of the titanium material in the longitudinal direction was in the range from approximately 50 μm to bring is Ino 70 μm in the lateral direction was in the range of from about 15 microns to about 20 microns.

Billet titanium material was subjected to forging, which included heating to 1100°, extrusion, deformation up to 130 mm, heated to 1050°, extrusion, deformation up to 130 mm and the cooling water. Next, the proposed method of production of a titanium material consisted of heating at TPP-40°, extrusion and deformation of up to 130 mm in Addition, the production method of the titanium material in accordance with the present invention include temperatures up to 1020°With deformation up to 130 mm and cooling in the water.

The proposed method for the production of titanium material includes forging in (α+β)-areas with an average speed of deformation 2×10-2with-1. The dimensions of the plate were equal to 230×435 mm was Used isothermal hydraulic press with a capacity of 1600 tons. The press was kept isothermal matrix node that was made of heat-resistant Nickel alloy and is heated to a temperature of billet titanium material, for example to a temperature in the range from approximately 400°With up to 450°C. At a temperature of approximately 980°C, billet titanium material was subjected to shrinkage by 50%. In addition, at temperatures of 850°and 950°performed further shrinkage, followed by rapid cooling. After three stages of deformation was carried out annealing at a temperature of 90° With that allowed us to obtain highly homogeneous microstructure with a grain size in the range from approximately 2 μm to approximately 5 μm. The total relative deformation, as measured by changes billet titanium material was equal to 16. End billet titanium material had a size of approximately 110×300 mm

Methods of production of titanium material in accordance with the present invention, including discussed above, allow to obtain products of titanium and design with suitable homogeneous microstructures of fine grains. The obtained titanium material is designed for various applications, for example, for the manufacture of nodes turbines and other components. Furthermore, the titanium material has a homogeneous microstructure with small grain, which can be easily tested methods and systems for ultrasonic testing.

Below is a General description of ultrasonic flaw detection with respect to titanium materials that can be obtained using different modes of production of a titanium material, including how the production of titanium material in accordance with the present invention. The subsequent discussion refers to titanium products and structures, which include titanium materials obtained according to the method of production is and titanium material in accordance with the present invention.

Titanium material obtained by the production methods of the titanium material in accordance with the present invention, can be tested to determine, include whether the microstructure of titanium material fine grained particles αTi. In addition, the titanium material may be used to form products and structures made of titanium material, which can be tested by ultrasonic testing to obtain a reliable indication uniform fine grain (RMZ) billets and forgings obtained from billets RMZ. Furthermore, the titanium material can ensure the production of products and structures made of titanium material in which the titanium articles and structures are, in General, "Rayleigh" scattering during ultrasonic flaw detection, which is indicative of a homogeneous microstructure with small grain in the titanium material. The functionality of scattering as a function of the size of the acoustic object and the wavelength of the ultrasound, smoothly change from one mode to another ("Rayleigh" to "phase" and "diffusion"). Adequate controls to detect critical defects and security prevailing Rayleigh scattering, acoustic object size must not be greater than approximately 1/10 of the length of the sound wave is used to control products. Formed Rayleigh scattering from the titanium articles and structures in accordance with the present invention is an indication that the titanium articles and structures contain uniform fine grain (RMZ). Thus, the titanium materials obtained in accordance with the present invention are suitable for various microstructure-sensitive applications, such as turbine units.

Therefore, a titanium material, which is obtained by means of the production of titanium material in accordance with the present invention, can be tested by ultrasonic testing with reliable results, because PM3-microstructure of titanium to form the dominant Rayleigh scattering. If ultrasonic inspection determines the scattering other than the dominant Rayleigh scattering, for example, only the phase scattering or phase scattering in combination with Rayleigh scattering, it is possible to determine such titanium articles and structures, as not having uniform fine titanium grain.

Particles αTi, basically, have a size less than 5 μm in diameter and, as a rule, are formed in the absence of crystallographic texture. The ability of ultrasonic flaw detection of these titanium materials with RMZ structure is characterized by a signal to the mind of machined blind holes. Signal-to-noise ratio, the received ultrasonic testing for titanium materials RMZ higher compared to conventional titanium materials. It was found that ultrasonic backscattering noise in RMZ titanium materials is much lower than in conventional titanium materials. In addition, when using the ultrasonic inspection of titanium articles and structures was found that the ultrasonic signal from machined blind holes in the titanium material RMZ has a higher amplitude than in conventional titanium materials.

In addition, ultrasonic inspection of titanium articles and structures indicates that the presence of colonies of particles (α+β)-structure associated with ultrasonic noise. For titanium materials with particle size less than about 10 microns, differences in size (α+β)particles, as a rule, do not have a significant impact on the generated ultrasonic noise. For example, the workpiece RMZ show, basically, Rayleigh scattering, while the usual blanks which do not have properties RMZ, during ultrasonic flaw detection demonstrate Rayleigh scattering plus phase scattering. Therefore, the ability to test containing titanium material increases, using titanium products and design the AI, which form the dominant Rayleigh scattering.

Titanium articles and structures, intended for liquid penetrant testing are microstructural RMZ characteristics and features that can be determined using the sensitivity to scattering of sound titanium products. The method of ultrasonic flaw detection involves the preparation of titanium articles and structures, for example, from an alloy Ti6242. This material alloy T is a typical example of the material for titanium products and designs in this invention. Description of Ti6242 alloy for titanium products and designs in no way intended to be limiting of the invention.

Titanium articles and structures (or "titanium material") are subjected to ultrasonic flaw detection, directing ultrasonic energy at a titanium material. Ultrasonic energy is directed into the material typically includes a sound pulse at certain frequencies. Scattering of sound pulse is determined by the frequency of the sound pulse, the characteristics of the microstructure of titanium material and natural physical characteristics, such as the elastic constant and the mass density of the titanium material. The scattered energy is then analyzed, and the characteristics of the ambient noise are determined by charactersare sound for titanium products and designs.

Titanium material for ultrasonic flaw detection contains material of uniform fine grain (RMP), which can be obtained by forging billet conventional titanium material in a variety of appropriate structures, configurations and shapes. For example, titanium articles and structures RMZ can be formed by forging press, by heat treatment, quenching and subsequent cooling. Titanium, which is actually subjected to ultrasonic flaw detection can be further prepared for titanium billet having at least one or, for example, a number of blind holes. These blind holes will serve as the standard brightness of picture elements (pixels), which can be used to calibrate the equipment for ultrasonic flaw detection.

The signal-to-noise ratio in the presence of defects in the machined blocks of Ti6242 strongly influenced by the conditions of formation of the microstructure of titanium, for example, when Ti6242 defined diffraction analysis of the backscattered electrons. Blocks Ti6242, having a microstructure that includes a uniform, thin, available from texture particles αTi, generally provide a ratio signal/noise by approximately 20 dB higher than the analogous titanium blocks with microstructures with colonies containing the crystallographically Viro the United particles α Ti.

The method and procedure for ultrasonic testing are described below with reference to the description of titanium products, structures and titanium materials, which are obtained according to the methods of production of titanium material in accordance with the present invention. In the discussion following special terms are used in their normal meaning understood by a person skilled ordinary skill in the art, unless otherwise stated. In addition, these dimensions are approximate, if not claimed that they are accurate.

Ultrasonic inspection provides control of titanium products and designs, made of alloy type Ti6242. Material Ti6242 is determined when this titanium material is made in four States microstructure: normal blank; conventional forging of a conventional workpiece; a workpiece with a uniform fine grain (RMP); and the forging of the billet RMZ. Individual blanks will be assigned to the above names, and all together they are referred to as "blanks".

Conventional workpiece has a diameter of approximately 23 cm. Conventional forging is a stamped disc, such as a forging in the form of a disk of the compressor. Procurement REP consists of two bars of profiles approximately 10×10×20 cm obtained from commercial zagotovka grains, improved using known processes reduce grain titanium alloy. The forging of the billet RMZ received forging press at temperatures of the order of 900°With approximately 7 cm in height, 6.35 cm diameter billet RMZ to approximately the final height 2,80 cm at a speed of pressing 2.5 cm/min Forged from billet RMZ subjected to heat treatment at a temperature of about 970°approximately one hour with cooling with helium at a temperature of about 705°C for approximately 8 hours, after which the workpiece is cooled in the air.

Then, the microstructure of each workpiece is checked using optical microscopy. Then crystallographic texture of each workpiece is determined using the analysis of the backscattered electrons (EBSP). Optical micrograph for each of the blanks shown in figure 1, where the notation (a) conventional procurement; the designation (b) - basic forging; the designation (s) - harvest RMZ; and designation (d) - forged billet RMZ. The figure 2 shows the "icosahedrally" image EBSP, which [0001] tilt pole scanned microstructure is presented in color. In the figure 2 colors are next to each other on adopted the "20-sided (icosahedrally) color sphere" and represent the slopes of the microstructure, which is similar to the slope of the field is. In addition, the figure 2 black pixel is a pixel, for which there can be no defined crystallographic orientation. In addition, the figure 3 drawn [0001] the pole for the areas scanned images of figure 2. Refer to figures 2 and 3 are similar to the legend of figure 1.

As shown in the drawings, the microstructure of the conventional workpiece contains primary particles αTi with a thickness of approximately 5 μm and a length in the range from about 5 μm to about 10 μm, as shown in figure 1 (a). Particles αTi organized in colonies, usually approximately 100 microns wide and approximately 300 microns in length, as shown in figure 2 (a). Phase orientation (α+β) scanned sample in figure 2 (a) illustrates the strong crystallographic texture with most [0001] the poles in the lower pane, as shown in figure 3 (a).

The microstructure of forgings from normal procurement contains primary particles αTi diameter in the range from approximately 5 μm to approximately 10 μm figure 1 (b). As shown in the drawing, there is a significant gap microstructure of the workpiece. Particles αTi is organized in large colonies with similar crystallographic orientation. For example, some colonies αTi have a width of approximately 300 μm and the length is often more than 1000 μm, as pok is shown in figure 2 (b). The phase orientation of the scanned sample αTi on figure 2 (b) has a strong crystallographic texture, which indicates that the majority of [0001], the poles are grouped into two polar regions, as shown in figure 3 (b). This strong group of poles suggests that the scanned region includes the two colonies.

Ultrasonic testing of a workpiece RMZ indicates a microstructure containing particles αTi. Particles have a diameter of about 5 μm, as shown in figure 1 (C). These particles αTi, apparently, are not grouped in the colony, as shown in figure 2 (C). Phase orientation αTi scanned sample, as shown in figure 2 (C)seems to be random, as shown in figure 3 (C).

The microstructure of the heat-treated forging billet RMZ shows that it consists of particles αTi. Particles αTi have a diameter of approximately 10 μm, as shown in figure 1 (d). These particles αTi exceeds the size of the particles of the workpiece from which the formed particles αTi, and this suggests that grain growth during at least one of forging or heat treatment of the workpiece RMZ. Particles αTi is not incorporated in the colony, as shown in figure 2(d). The phase orientation of particles αTi seems random, as shown in figure 3(d).

Ultrasonic characteristics of the blanks forming the different Titus the new products and designs, define C-scan blocks formed from blanks of titanium articles and structures. Titanium articles and structures made of blocks with blind holes with a diameter of approximately 0,79 mm Titanium blocks have a thickness of approximately 38 mm and have holes that are drilled so that the bottom of the hole was terminated at a distance of approximately 25 mm to the upper surface of the block. Every regular harvesting, conventional forgings and billet RMZ have the size of the surface approximately 64×64 mm (area of square) and each of them also has 9 blind holes on the bottom surface. Forgings made from a material RMZ had dimensions of approximately 64×28 mm and had 6 blind holes. Each titanium block is processed mechanically to the desired orientation so that the direction of the ultrasonic flaw detection was similar to that of a larger component, formed of titanium articles and structures. For example, the thickness of the titanium block 38 mm measured in the radial direction of the billet or forging.

Ultrasonic transducers used for ultrasonic flaw detection, process C-scan are shown in table 1. Table 1 also shows the characteristics of ultrasonic sensors. The sensors use a piezoelectric element containing PVC skin (PVC). the Central frequency of the ultrasonic sensors is measured signals, reflected from the rear wall of the block of quartz glass.

Were performed in two separate series of ultrasonic C-scan immersion blocks containing titanium. A series of ultrasonic C-scan was performed at a nominal frequency of approximately 5 MHz, 10 MHz and 20 MHz. One scan on each of these frequencies was performed to measure the signal from the blind holes in the block. The second scan of each of the above frequencies was performed at high magnification, to get the statistics of sensitivity to scattering noise and sound.

Each of the scans were performed on a square area of approximately 147,5 mm in length and width, when scanning 0,144 mm and increment index. The sound is focused approximately at the point 25 mm below the top surface of the blocks, approximately at the location of the blind holes on the bottom surface. The width of the scanning signal was equal to approximately 4 microseconds. The obtained image-scan consisted of approximately 1024×1024 pixels.

The figure 4 presents images From a scan performed with a frequency of approximately 5 MHz. In figure 4 the material RMZ workpiece is in the upper left corner, the usual procurement is at the top of the rights of the m corner conventional forging is in the lower left corner and the forging of the material RMZ is in the lower right corner. Conventional billet and forging demonstrate more intense interference, which indicated a more vivid picture elements in these blocks, as shown in figure 4. Lower intensity characteristic of the blind holes on the bottom surface, as indicated by the lower intensity of the picture elements of these areas, as shown in figure 4.

Quantitative measurement of signal and interference signal and noise can be determined from the results of the scan. The signal from each blind hole is taken as the brightest pixel in the array 3×3 of the nine brightest pixels. Statistics of noise and sensitivity to scattering of sound can then be determined from the square array of pixels that do not include blind holes. Quantitative data are presented in table 2. The signal in table 2 is the average signal from all the blind holes on the bottom surface in the corresponding block. Signal-to-noise ratio is calculated as:

(the average signal to noise ratio) - (maximum noise average noise), as well as:

(the average signal to noise ratio)-3 σnoise).

Data for the calculation of the ratio signal/noise for titanium materials are given in table 3. Ka is described above, both calculations provide a measurement of the intensity of the signal in the selected block relative to the impulse noise in the same block.

Accordingly, if the detection value of the signal-to-noise ratio is carried out by expression (average signal-to - medium noise) - (maximum noise medium noise), it can be concluded that the material contains uniform fine grain at a frequency 6,62 MHz if signal-to-noise ratio for the signal from the hole diameter of 0.79 mm to 25 mm below the test material surface at least equal to 20; frequency 11,36 MHz signal-to-noise ratio at least equal to 50; and on the frequency 18,43 MHz signal-to-noise ratio, at least equal to 50. In addition, if the definition of the signal-to-noise ratio is carried out, using the expression (average signal to noise ratio) - 3 σnoisefor blind holes on the bottom surface, we can also come to the conclusion that the material contains uniform fine grain on the frequency 6,62 MHz if signal-to-noise ratio at least equal to 50; frequency 11,36 MHz signal-to-noise ratio at least equal to 100; and on the frequency 18,43 MHz signal-to-noise ratio at least equal to 150. Each of these signal to noise matches the given noise level, as determined by pre-drilled holes with the material.

The high signal from the blind holes on the bottom surface was measured at harvest RMZ and the low signal from the blind holes on the bottom surface was measured in a conventional forging, as shown in the graph of figure 6. The highest average noise maximum noise and the largest standard deviation of the noise were measured in conventional procurement. The lowest average noise, the small maximum noise and the small standard deviation of the noise were measured in the forging of the material RMZ, as shown in the graph of figure 7. Accordingly, we can conclude that the forging material RMZ has the highest signal-to-noise ratio and that a conventional forging has the lowest signal-to-noise ratio, as shown in the graph of figure 8.

When the ultrasonic inspection of titanium articles and structures of the velocity of sound in the longitudinal direction were measured during the extrusion T. Pressing Ti6242 was executed to create a strong texture in the direction of pressing. For example, pressing T was carried out at a temperature of 1040°and when the ratio is approximately 8:1. Extruded product is then subjected to heat treatment at a temperature of about 593°C for approximately 8 hours. X-ray examination and analysis helped to determine the grain and the orientation of the microstructure 116242. This and the following and analysis of Ti6242 indicate a strong texture in the direction of extrusion with the intensity in the direction of pressing. The intensity was determined by a random selection of approximately 22 times.

Ultrasonic behaviour of a small titanium articles and structures, for example, from an alloy Ti6242 can be determined with ultrasonic inspection of titanium articles and structures as a function of frequency ultrasound and microstructure of the material.

The speed of sound in αTi is approximately 6 mm/s At a frequency of 5 MHz ultrasound wavelength in the titanium articles and structures is equal to approximately 1.2 mm, the Size of the colony, greater than 200 mm, can change the nature of the scattering from Rayleigh to stochastic (phase). The speed of sound in Ti6242 measured on rectangular parts of Ti6242, which are made of respective workpieces Ti6242. A rectangular part of Ti6242 have a length of approximately 16 mm in the direction of extrusion and a length of approximately 12 mm in the direction perpendicular to the direction of pressing. The longitudinal velocity is measured at a frequency of about 10 MHz, using the contact sensor, the amplifier and the oscilloscope. The longitudinal velocity is determined by measuring the transit time of a sound pulse in the selected direction and back. The speed of sound in the direction of extrusion of approximately 6,28 mm/s; while the speed of sound in the direction perpendicular to the direction of extrusion of approximately 6.1 mm/s

<> The results of ultrasonic testing and intentions of titanium articles and structures, along with the characterization of the microstructure of titanium articles and structures based on the use of test blocks blanks RMZ, which is formed of conventional material, as described above. In the process RMZ receive the samples in which the original structure of the colonies αTi in a conventional workpiece removed. Stage forging material RMZ 900°and reducing a height of approximately 60% did not lead to the creation of colonies αTi or the development of a strong texture and αTi microstructure.

As shown in figures 6 and 7, the differences in sensitivity to scattering of sound and noise, mainly depend on the frequency. This dependence suggests that the magnitude of the scattering object, for example, the size of the colony, in the usual material increases the contribution to the sensitivity to scattering of sound and the attenuation of the phase scattering. This change in input is not a complete transition from one mechanism clean scattering to another scattering mechanism, such as a transition mechanism from Rayleigh scattering to the mechanism of phase dispersion, since such a change would give a slope of about - 2 figure 5.

Particle size αTi, basically, is not significant in any definition of the signal-to-noise ratio, since the size of ASTIC α Ti is the same in all materials and mostly smaller than the ultrasonic wavelength. The difference in various materials, scanned with ultrasonic flaw detection can be explained by the presence of large colonies in the usual billets and forgings. Note that this difference in the speed of sound in compressed samples Ti6242 is approximately 6 mm/sec. As a rule, this rate corresponds to a wavelength of the ultrasonic flaw detection is of the order of 1.2 mm at a frequency of approximately 5 MHz, about 600 mμ at a frequency of about 10 MHz and about 300 mμ at a frequency of approximately 20 MHz. Hence, the sizes of colonies in conventional procurement, and forging comparable with the wavelength of the ultrasound.

Relative contributions of Rayleigh scattering and scattering phase depend on the frequency, for example, in an ultrasonic frequency band. This dependence on frequency at least partially attributed to the fact that the wavelength of 300 μm at a frequency of approximately 18.43 MHz is approximately equal to the thickness of the colony αTi. The wavelength of 900 μm at a frequency of MHz is approximately 6.62 MHz is approximately three times the size of the colony. Scattering with frequency 6.62 MHz is in the range of scattering phase for its contribution, while scattering with frequency 18.43 MHz provides, in General, the contribution to the scattering phase.

Forging material RMZ leads to several b is lsamo grain size, than the original piece. However, the forging of the material RMZ has lower noise and higher signal intensity, as shown in table 2. This behavior can be attributed to a slightly lower volume fraction of particles αTi forged material, as illustrated in the figure 1 legend (C) and (d).

Conventional forging has a lower noise level than conventional procurement, but it has a lower signal-to-noise ratio, which may be partly due to a weak signal from the blind holes on the bottom surface. Conventional forging has a lower volume fractions of particles αTi than the workpiece. Weaker signal in a conventional forging can be caused by at least partial attenuation of sound passing through a heavily textured areas. The size of the reflecting object colonies αTi, amounting to approximately 1 mm in length and approximately 300 microns in width, normal to the workpiece and the forging can lead to scattering in the phase component. Similarly, it is possible that the structure of the colony αTi on blind holes on the bottom surface will scatter the reflection of sound from blind holes.

The microstructure of the billet RMZ and forgings made from billets RMZ include fine grained particles αTi. These particles αTi typically have a diameter less than 5 μm, as a rule, the ri absence of crystallographic texture. Ultrasonic flaw detection is characterized by the fact that the signal-to-noise machined blind holes is much higher in the material RMZ than in conventional materials. Materials RMZ interference from backscattering of ultrasound lower than in conventional materials. In addition, the ultrasonic signal from machined deaf holes stronger than RMZ material.

The presence of the structure of the colony αTi is associated with the ultrasonic noise generated by the ultrasonic inspection of titanium articles and structures in accordance with the present invention. For materials with particle size less than 10 microns differences in particle size αTi, as a rule, do not have a significant impact on the formation of ultrasonic noise. For example, the workpiece RMZ, which may be formed according to the method of production of a titanium material in accordance with the present invention, may exhibit mainly Rayleigh scattering, while the usual blanks that do not have properties RMZ demonstrate Rayleigh scattering plus phase scattering. Scan quality containing titanium material increases with the prevailing Rayleigh scattering.

Although there have been described various variants of the invention, it should be understood that specialists in this area can be made the s various changes or improvements and modifications of the elements of the invention.

1. Method for the production of homogeneous fine-grained titanium material, characterized in that it comprises the production of billets of titanium material, the first heat treatment of the workpiece by heating up to β-field, rapid cooling of the workpiece from β-field $ (α+β)-region, forging blanks with the creation of the deformation process titanium material conditions of superplasticity and the second heat treatment by recrystallization annealing to obtain a grain size in the range from approximately 5 μm to approximately 20 μm.

2. The method according to claim 1, characterized in that the heating of the workpiece by the first heat treatment is carried out to a temperature in the range from approximately 600°With up to approximately TPPwhere TPP- temperature polymorphic phase transformation of titanium material.

3. The method according to claim 1, characterized in that the workpiece of titanium material produced by powder metallurgy methods.

4. The method according to claim 1, characterized in that the receive homogeneous fine-grained titanium material mainly with equiaxial grains of titanium, one size.

5. The method according to claim 1, characterized in that the receive homogeneous fine-grained titanium material mainly with uniform distribution of particles of the second phase and alloying elements.

6. The way is about to claim 1, wherein the receive preparation of two-phase titanium material.

7. The method according to claim 1, characterized in that the first heat treatment of the workpiece material titanium alloy is carried out by heating the workpiece to approximate 1200°for approximately one hour.

8. The method according to claim 1, characterized in that the heating of the workpiece by the first heat treatment is carried out to a temperature in the range from about 875°With up to a temperature of approximately 1200°C.

9. The method according to claim 1, wherein the forging is carried out by deforming the workpiece in isothermal press.

10. The method according to claim 9, characterized in that the deformation is carried out in several operations.

11. The method according to claim 1, characterized in that the receive homogeneous fine-grained titanium material with a grain size in the range from about 15 microns to about 20 microns.

12. The method according to claim 1, wherein the forging is carried out on the press by conducting at least one of the following operations: bending, forging the square.

13. The method according to claim 1, wherein the forging is carried out by repeated deformation.

14. Method for the production of homogeneous fine-grained titanium material, characterized in that it includes obtaining procurement of two-phase titanium material, the first t is micescu processing of the workpiece by heating up to β -region to a temperature in the range from approximately 600°With up to approximately the temperature of polymorphic phase transformations in titanium material (TPP), rapid cooling of the billet titanium material from β-field $ (α+β)-region, forging blanks with the creation of the deformation process titanium material conditions of superplasticity and the second heat treatment by recrystallization annealing with obtaining a two-phase titanium material with a grain size in the range from about 15 μm to about 20 μm, consisting mainly of equiaxial grains of titanium of the same size and evenly distributed particles of the second phase and alloying elements.



 

Same patents:

FIELD: manufacture of semi-finished sheet product from low-plasticity two-phase titanium alloy of submicrocrystalline structure suitable for low-temperature superplastic deformation.

SUBSTANCE: method involves rolling blank with prepared structure at temperature below polymorphic transformation temperature under isothermal or quasi-isothermal conditions provided by heating of rolls. Grain size stabilization and isotropic properties are reached thanks to the fact that rolling process is provided in low-temperature superplastic deformation mode: at first passage deformation is carried out at the extent of ε≥εmin, where εmin is minimum extent at which structural state of alloy is formed in selected temperature-rolling speed mode. Such structural state is necessary for enabling of cooperated grain boundary sliding during deformation. After each subsequent passage of rolling step, blank is cooled for fixing of structural state provided upon deformation. During heating of blank in furnace for subsequent passage of rolling step, heating time is limited in order to avoid disturbance of structural state of alloy produced at previous rolling passage.

EFFECT: increased efficiency and improved quality of semi-finished sheet product fit for further low-temperature superplastic deformation.

12 cl, 9 dwg, 1 tbl, 7 ex

FIELD: non-ferrous metallurgy, namely thermal-mechanical working of titanium alloys, possibly manufacture of sheets of high-strength β-titanium alloys by rolling process.

SUBSTANCE: method for producing sheets comprises steps of hot pressing of ingot to slab; processing slab; subjecting it to hot and cold rolling and to heat treatment. Hot pressing of ingot to slab is realized at temperature exceeding by 400-440°C temperature value Tpc of polymorphous conversion. Hot rolling is realized by three stages. At first stage rolling is performed at temperature exceeding by 400 - 430°C temperature Tpc at total deformation degree 71 - 95%. At second stage rolling is performed at temperature exceeding by 60 - 80°C temperature value Tpc at total deformation degree 20 - 30% with single reduction values 3 - 5%. At third stage rolling is performed at temperature exceeding by 160-180°C temperature value Tpc with total deformation degree 51 - 90% and single reduction values 5 - 7%. Then annealing is realized at temperature exceeding by 80 - 180 °C temperature value Tpc and cooling in temperature range 750 - 350°C with deformation rate 100-300°C/min is performed. Cold rolling is performed at total deformation degree 8 - 20%.

EFFECT: increased stabilized strength and ductile properties of materials.

FIELD: non-ferrous metallurgy, namely thermal-mechanical working of hard-to-form high-strength β-titanium alloys, possibly manufacture of thin sheets by rolling.

SUBSTANCE: method comprises steps of mechanically working surface of slab; subjecting it to hot, warm and cold rolling; annealing and aging it. After mechanical working, slab is subjected to scooping and to hot rolling during two stages. At first stage rolling is realized at polymorphous conversion temperature Tpc + (380 - 400)°C and at total deformation degree 85.0 - 95.0% and then blank is subjected to further annealing at temperature Tpc + (145 - 165)°C. At second stage rolling is realized at temperature Tpc + (100 - 120)°C with total deformation degree 45.0 - 55.0% and to further annealing in temperature range Tpc + (50 - 165)°C. Warm rolling is realized at temperature Tpc + (10 - 30)°C with total deformation degree 40 - 60 % for further annealing in temperature range Tpc + (70 - 100)°C. Cold rolling is performed at total deformation degree 50.0 - 55.0%.

EFFECT: improved stable strength and ductile properties of material.

FIELD: aerospace industry; nonferrous metallurgy; other industries; methods of the thermomechanical processing of the articles made out of the titanium alloys.

SUBSTANCE: the invention is pertaining to the field of nonferrous metallurgy, in particular, to the thermomechanical processing of the articles made out of the titanium alloys and may be used in the aeronautical engineering for manufacture of the skins, envelopes, containers, partitions, the bottoms. The invention presents the method intended to up-grade the level of the mechanical processing of the articles, which provides for the thermomechanical processing of the articles made out of the titanium alloys, including their multiple heatings up to the temperature of above or below the temperature of the polymorphic transformation Тtp and deformation. The thermomechanical processing includes nine phases. At that at the first phase they conduct the heating of the titanium alloy up to the temperature of(Ttp +230 ÷ Ttp +270)°С, its deformation with the level of 50÷90 %; at the second phase - the heating up to the temperature of(Ttp - 20 ÷ Ttp-40)°С, the deformation with the deformation level of 30÷60 %; at the third phase - heating up to the temperature of (Ttp +60 ÷ Ttp+160)°С, the deformation with the level of 20-60%; at the fourth phase - heating up to the temperature of (Ttp-10 ÷ Ttp -40)°С, deformation with the level of 40-70%; at the fifth phase - heating up to the temperature of(Ttp -40 ÷ Ttp+200)°С, the deformation with the level of 65-95 %; at the sixth phase - heating up to the temperature of (Ttp -100 ÷ Ttp -160)°С, the deformation with the level of 40-70 %; at the seventh phase - heating up to the temperatures of(Ttp-100 ÷ Ttp -160)°С, the deformation with the level of 20-50 %; at the ninth phase - hearing up to the temperature of (Ttp -150 ÷ Ttp -190)°С, the deformation with the level of 2-5 %.

EFFECT: the invention ensures the increased level of the mechanical properties of the articles made out of the titanium alloys.

1 tbl, 3 ex

FIELD: nonferrous metallurgy; aircraft industry; other industries; methods of the thermomechanical processing of the articles made out of the titanium alloys.

SUBSTANCE: the invention is pertaining to the field of nonferrous metallurgy, in particular, to the thermomechanical processing of the articles made out of the titanium alloys and may be used in the aeronautical engineering. The invention presents the method of thermomechanical processing of the articles made out of the titanium alloys providing for their multiple heatings up to the temperature of above or below the temperature of the polymorphic transformation Ttp and deformation in the process of cooling to the temperature below Ttp, aging and cooling. The thermomechanical processing includes eight phases. The first phase includes the heating of the titanium alloy up to the temperature of (Ttp+280÷Ttp+350)°С, its deformation within four runs at cooling up to the temperature of (Ttp-4О÷Ttp-100)°С with the change of the deformation direction by 90° at alternation of the yielding and drawing with the deformation level of 20÷50 % at each run; at the second phase - exercise heating up to the temperature of(Ttp+100÷Ttp+160)°С, the deformation in four runs at cooling to the temperature of (Ttp-100÷Ttp-180)°С with the change of the deformation direction by 90°С at alternation of the yielding and drawing with the deformation level of 20÷50 % at each run; at the third phase - heating up to the temperature of(Ttp-20÷Ttp-40)°С, the deformation by yielding with the level of 20-60% in the process of cooling to the temperature of (Ttp-110 ÷ Ttp -130)°С; at the fourth phase - heating up to the temperature of(Ttp + 20÷Ttp -50)°С, deformation by drawing with the level of 30-70% in the process of cooling to the temperature of(Ttp -110 ÷ Ttp-130)°С; at the fifth phase - heating up to the temperature of(Ttp -20 ÷ Ttp-40)°С, the deformation by yielding of with the level of 20-60 % in the process of cooling to the temperature of(Ttp -110 ÷ Ttp -130)°С; at the sixth phase - heating up to the temperature of (Ttp +100 ÷ Ttp +130)°С, the deformation by drawing at the rolling with the level of 55-80 %; at the seventh phase - heating up to the temperatures of(Ttp -20 ÷ Ttp -40)°С, the deformation by drawing at the rolling with the level of 30-40 %; at the eighth stage - heating up to the temperature of(Ttp -360 ÷ -500)°С with the aging for 5-20 hours. The technical result of the invention is the increased level and the decreased anisotropia of the mechanical properties of the articles.

EFFECT: the invention ensures the increased level and the decreased anisotropia of the mechanical properties of the articles.

1 tbl, 2 ex

FIELD: aerospace industry; rocket industry; other industries; methods of the thermomechanical processing of the articles made out of the titanium alloys.

SUBSTANCE: the invention is pertaining to the field of nonferrous metallurgy, in particular, to the thermomechanical processing of the articles made out of the titanium alloys and may be used in the aeronautical engineering and rocketry for production of the containers, girders, longerons, bulkheads, landing gear and fastening components. The invention presents the method intended to up-grade the level of the mechanical processing of the articles, which provides for the thermomechanical processing of the articles made out of the titanium alloys, including their multiple heatings up to the temperature of above or below the temperature of the polymorphic transformation Ttp and deformation. The thermomechanical processing includes seven phases. The first phase includes the heating of the titanium alloy up to the temperature of(Ttp+200÷Ttp+270)°С, its deformation within four runs with the change of the deformation direction by 90°C at alternation of the yielding and drawing with the deformation level of 20÷50 % at each run of the deformation; at the second phase - they exercise heating up to the temperature of(Ttp+170÷Ttp+230)°С, the deformation in four runs with the change of the deformation direction by 90°С at alternation of the yielding and drawing with the deformation level of 20÷40 % at each run of the deformation; at the third phase - heating up to the temperature of (Ttp-20÷Ttp-40)°С, the deformation by yielding with the level of 20-60%; at the fourth phase - heating up to the temperature of(Ttp + 60 ÷ Ttp + 120)°С, deformation with the level of 20-60%; at the fifth phase - heating up to the temperature of(Ttp -20 ÷ Ttp-40)°С, the deformation with the level of 20-60 %; at the sixth phase - heating up to the temperature of (Ttp +30 ÷ Ttp +90)°С, the deformation with the level of 20-60 %; at the seventh phase - heating up to the temperatures of(Ttp -20 ÷ Ttp -40)°С, the deformation with the level of 20-50 %.

EFFECT: the invention ensures the increased level of the mechanical properties of the articles made out of the titanium alloys.

2 cl, 1 tbl, 3 ex

FIELD: manufacture of intermediate blanks from α- and α+β-titanium alloys by hot deformation method.

SUBSTANCE: proposed method includes forging an ingot into bar during several passes at temperature of β- and (α+β) field. Then, blank is subjected to machining and two-stage heating. At the first stage, blank is heated to temperature of its surface which is below polymorphous transformation temperature by 250 C and is above polymorphous transformation temperature by 100 C; heating is performed at rate of 0.3-2.5°C/s. At the second stage, blank is cooled down or heated to temperature which is below polymorphous transformation temperature by 40-250 C. Final molding is performed in (α+β) field at forging reduction ratio at last passes of 1.36-2.5.

EFFECT: reduction of blank heating time to molding temperature; increased productivity; possibility of obtaining fine-grain structure of blank metal.

2 cl, 3 ex

FIELD: nonferrous metallurgy; other industries; methods of manufacture of the titanium sheets with the improved decorative-protective properties.

SUBSTANCE: the invention is pertaining to the method of treatment of the surfaces of the sheets made out titanium and its alloys, which may be used for improvement of their decorative-protective properties. The method includes the hot rolling, the cold rolling and the annealing of the sheets. At that after annealing the surface of the sheets is exposed to the acid etching in depth of not less than 0.04 mm, to the subsequent clarification in the nitric acid solution, after which exercise the final multirun cold rolling of the sheets in the polished rolls with the rolling speed of 0.65-0.75 m\s at total compression of 0.3-0.35 mm. The technical result of the invention is production on the surface of the sheets made out of titanium and its alloys of the homogeneous oxide film without pores, without spalls, without cracks, with the minimal roughness and the high reflective properties.

EFFECT: the invention ensures production on the surface of the sheets made out of titanium and its alloys of the homogeneous oxide film without pores, without spalls, without cracks, with the minimal roughness and the high reflective properties.

2 cl, 3 ex

FIELD: plastic working of metals, namely processes for manufacturing rods of titanium alloys used, for example for manufacturing fastening parts.

SUBSTANCE: method comprises steps of hot rolling billet formed of ingot; etching formed rod, subjecting it to vacuum annealing, daring, subjecting drawn rod to air annealing for two stages and mechanically working for final size. In first variant of invention air annealing is performed at first at temperature 650 - 750°C for 15 - 60 min at cooling in air till 20°C and then at temperature 180 -280°C for 4 - 12 h at cooling in air till 20°C. According to second variant of invention air annealing is realized at first at temperature 750 - 850°C for 15 - 45 min at cooling in furnace till 500 - 550°C and then cooling in air till 20 °C.

EFFECT: homogenous structure along rod section, increased rupture limit strength and percentage elongation, lowered labor- and power consumption.

2 cl, 1 tbl, 2 ex

FIELD: metallurgy; power engineering industry and instrumentation engineering.

SUBSTANCE: proposed method enhances deformation characteristics of convertible form change such as ductility of direct transformation and memorized-shape effect due to use of thermocyclic aging in unloaded state at stage of heating from temperature t= 298K to temperature t= 500K and at constant moment of forces at stage of cooling to temperature t= 298K.

EFFECT: enhanced efficiency.

1 tbl

FIELD: plastic working of metals, possibly manufacture of blanks designed for producing hollow thin-wall articles such as aluminum tubes, bottles.

SUBSTANCE: method comprises steps of feeding initial predetermined-size material to pressing machine having working units. In said working units initial material is subjected to successive parametric pressing by transitions. Pressing is realized at speed directly proportional to specific pressure of pressing process according to relation: Vt = KPt where Vt -parametric pressing speed at time moment t; Pt - specific pressure of pressing process at time moment t; K = (Pend - Pst)tk - proportionality coefficient; Pend - specific pressure at pressing process termination; Pst - specific pressure at pressing process starting; tk - time period of pressing process.

EFFECT: improved quality of blanks, enhanced efficiency of production of ready articles.

2 cl, 1 dwg

FIELD: pressure shaping; manufacture of blanks from materials at preset structure including submicro-crystalline structure and nano-crystalline structure at respective level of physico-mechanical properties.

SUBSTANCE: proposed method consists in successive deformation cycles of initial blank by compression in height, thus obtaining blank with lateral faces. Proposed method ensures smooth plastic flow of material of blank in opposite directions along axis perpendicular to direction of application of deformation force. Each deformation cycle includes placing the blank in device, subjecting it to deformation, withdrawing the blank from device and re-setting for next cycle. Device proposed for realization of this method has working part with cavity and upper and lower punches. Working cavity consists of two parts: upper and lower. Lower part is widened along one of its horizontal axes.

EFFECT: enhanced homogeneity of ultrafine-grained structure at improved mechanical properties.

9 cl, 4 dwg, 1 tbl, 1 ex

FIELD: plastic working of metals, possibly production of forged pieces.

SUBSTANCE: apparatus for making forged pieces having length to diameter relation more than 3 includes power hydraulic cylinder on plunger of which upper striker is mounted. Lower striker is mounted in rotary mechanism. The last is in the form of kinematics pair having gear wheel and racks rigidly secured to plungers of hydraulic cylinders. Apparatus also includes second power hydraulic cylinder whose plunger is mounted in gear wheel with possibility of axial motion and rigidly joined with lower striker. Both power hydraulic cylinders separately through pipelines and throttles are communicated with respective hydraulic cylinders of rotary mechanism.

EFFECT: improved design of apparatus, increased degree of plastic deformation of blank at its single mounting operation in apparatus.

2 dwg

FIELD: plastic working of metals, possibly realization of blank working operations designed for developing high technology of thermo-mechanical working.

SUBSTANCE: apparatus includes housing where lower stop and both movable relative to housing punch and upper stop are arranged. Said stops have notched surfaces for engaging with blank and their ends are in contact respectively with punch and supporting plate. Stops may move relative to punch and supporting plate in mutually opposite directions normal relative to axis of housing. Apparatus is also provided with two wedges. Housing may move relative to supporting plate and it includes two annular grooves arranged in upper and lower parts of housing and designed for placing said wedges. Upper and lower stops form with wedges wedge pairs.

EFFECT: simplified design of apparatus, increased efforts applied to blank.

1 dwg

FIELD: pressure treatment of materials, particularly to obtain parts with predetermined service performance level by cold plastic deforming thereof.

SUBSTANCE: method involves arranging cylindrical billet in matrix interior on shpero-dynamic fluctuation module so that the billet is supported by pusher, wherein the module comprises cavity with main resonator located in the cavity; performing double-sided billet deformation from the opposite directions thereof, wherein from upper billet end the billet is deformed by applying rolling force thereto by means of die, from lower billet end the billet is deformed by applying summary pulsed force of shpero-dynamic fluctuation module and main resonator. Additional resonator is freely installed in module interior to apply additional percussion force to lower billet end during billet deformation.

EFFECT: provision of wavy plastic deformation and creation of "artificial intelligence" zones in billet.

1 dwg

FIELD: metal working by ultrasonic forging; manufacture of blades at enhanced technical and service characteristics.

SUBSTANCE: edge of plate is placed between taper surfaces of strikers located opposite each other for forming wedge-shaped blade and is subjected to deformation by ultrasonic forging. Plate is moved relative to longitudinal axes of strikers in transversal direction. Strikers connected with ultrasonic oscillation source are rotated about their longitudinal axes with the aid of drive. Taper working surface of each striker has recess whose generatrix corresponds to shape of surface of wedge-shaped blade.

EFFECT: improved quality of tool cutting edge; increased productivity; enhanced wear resistance of fittings.

19 cl, 9 dwg

FIELD: metallurgy; production of semi-finished products from high-temperature high-alloy wrought nickel-based alloys for manufacture of disks for gas-turbine engines working at temperatures higher than 600°C.

SUBSTANCE: proposed method includes preliminary deformation of blank by upsetting by two or more times, final deformation and heat treatment; first upsetting is performed in closed container; during next upsetting, technological metal ring at temperature of (0.02-0.5)Tdef. is placed on blank heated to deformation temperature Tdef. and free upsetting is performed in stamp tool heated to deformation temperature. Geometric parameters of ring are selected from given relationships. Preliminary deformation of blank is performed at intermediate annealing. Height-to-diameter ratio of starting blanks is no less than 3:1. Proposed method ensures forming of homogeneous fine-grain structure over entire volume of blank due to work in end zones.

EFFECT: simplified procedure; reduced labor consumption.

4 cl, 1 tbl, 5 ex

FIELD: plastic working of materials, possibly cold plastic deforming of parts with predetermined level of operational characteristics.

SUBSTANCE: method comprises steps of placing cylindrical blank in cavity of lower die on sphere-dynamic fluctuation module and resting part by means of pusher; deforming part by rolling-around punch; imparting to said punch and to pusher motion along curves in the form of logarithmic helixes rising in the same direction. It provides realization of wave structure of plastic deformation and obtaining in blank of material zones of "artificial intellect".

EFFECT: possibility for producing parts with desired level of operational characteristics.

1 dwg

FIELD: plastic working of materials, possibly cold plastic deforming of parts with predetermined level of operational characteristics.

SUBSTANCE: method comprises steps of placing blank onto support; end upsetting of blank and then deforming it with punch; subjecting punch to complex motion in the form of circular rolling out at simultaneous cyclic axial rocking; subjecting blank at side of its support to cyclic striking pulses acting along helical path. Due to such complex motion of punch blank is deformed by value consisting of 5 - 7 % of predetermined deformation degree. Then motion of cyclic axial rocking of punch is interrupted and pulse effort is applied to punch at frequency equal to that of forced oscillations of support. Blank is subjected to finish shaping by rolling it out with use of punch without pulse efforts. Invention provides wave nature of plastic deformation, penetration of rotor to nano-level of blank material for forming in it massifs of material of "artificial intellect".

EFFECT: possibility for forming desired operational properties in material of blank.

1 dwg

FIELD: plastic metal working.

SUBSTANCE: invention can be used at plastic shaping of parts by orbital deformation method. Blank is made previously profiled in form of cylinder with ring flange. Dimensions of blank are defined by mathematical expression given in invention. Blank is placed between die and spherodynamic fluctuating deforming module and then is spinned. Ring flange of blank is made for providing its arrangement between die and said deforming module with clearance. Size of clearance between ring flange and die exceeds clearance between ring flange and deforming module by a factor of 10.

EFFECT: provision of deformation resonance in material in process of machining for realizing wave plasticity character in form of rotary modes of plasticity.

2 dwg

FIELD: plastic working of metals in different branches of industry.

SUBSTANCE: apparatus includes supporting plate and housing with openings and duct. Punch, upper and lower stops are mounted in housing. Said stops may be in contact with blank by their flat notched surface. Movable lower stop is arranged in openings of housing and on supporting plate; it engages with said plate by its smooth surface. Hydraulic cylinder joined by its rod with lower stop is mounted on supporting plate. Upper stop is in the form of cylinder mounted in housing in such a way that it restricts together with punch inner cylindrical cavity of hydraulic system providing motion of lower stop. Said hydraulic system also includes duct of housing and hydraulic cylinder.

EFFECT: enlarged manufacturing possibilities of apparatus due to increased range of changing relation of shear deformation to compression deformation of blank.

2 dwg

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