Thin piece of beta-titanium or quasi-beta-titanium alloy and a method of manufacturing such thin piece using forging technique
FIELD: nonferrous metallurgy.
SUBSTANCE: invention provides axially unsymmetrical pieces with thickness less than 10 mm and made from β-titanium or quasi-β-titanium alloy. Microstructure of the core is formed by whole grains having degree of extension above 4 and equivalent diameter 10 to 300 μm. Manufacturing method envisages providing emailed blanc, converting it, if necessary, into elongated piece, forging elongated piece, hardening forged elongated piece, and annealing hardened forged elongated piece. Such piece can, for example, be a blade for turbine compressors. Optimal geometry enables improvement of aerodynamic properties and thereby working characteristics of engine, wherein the piece is utilized.
EFFECT: improved performance characteristics and prolonged service time.
12 cl, 2 dwg
The technical field to which the invention relates.
The present invention relates to a thin alloys of β-titanium or quasi-β-titanium, as well as to the method of manufacture of such products.
More specifically, the invention relates to products, axially asymmetric, having a thickness less than 10 mm and made of alloys β-titanium or quasi-β-titanium, as well as to method of manufacture, which is characterized by the fact that based on the forging operation.
The level of technology
The development of the present invention is related to solving problems of manufacturing monobloc vaned disk (BN) with blades that are mounted by the method of linear friction welding or soldering. Such monobloc vaned discs are usually made of alloys β-titanium or quasi-β-titanium with regard to the required mechanical properties, namely their durability to vibration fatigue. Currently, such products are produced by machining solid material (see, for example, U.S. patent No. 5326409).
In regard to the manufacturing method of forging blades such disks from alloys β-titanium or quasi-β-titanium there is a biased opinion. It is considered a priori that forging structures of alloys β-titanium or quasi-β-titanium, i.e. coarse-grained structures, to develop small products is oldini (blades) can only lead to the production of items with low mechanical properties (against shock loads and strength vibration fatigue). In this regard, in the manufacture of blades for blade disks (in particular, compressor disks) from alloys β-titanium using forging the known methods of manufacture of the blades, including the method according to U.S. patent No. 4505764 (which can be regarded as the closest analogue of the present invention), include the use of more complex operations, heat treatment, aimed at improving the structure of the alloy.
In an unexpected way in the framework of this invention the blades (fine products) from alloys β-titanium or quasi-β-titanium, high performance (i.e. defect-free in metallurgical terms, and with good mechanical characteristics), were obtained by the forging method, i.e. with a material saving in comparison with the classical method of machining. These blades have a higher durability compared to blades, manufactured by machining. In addition, there may be obtained the optimized geometry of the blades to improve their aerodynamic properties, and hence the operating characteristics of the engine in which they are used.
Thus, the invention was conceived and developed a non-obvious manner with respect to manufacturing monoblock love the internal disks (BN). It is not limited to this application, and naturally can also be used in more or less related fields, such as manufacturing monoblock blade rims (IM), repair monobloc vaned disk (BN) and monoblock blade rims (IM), and, more broadly, for the manufacture of thin articles from alloys β-titanium or quasi-β-titanium.
Mastering the method of forging in accordance with the invention as applied to workpieces of alloy β-titanium or quasi-β-titanium allowed to get slim products of these alloys β-titanium or quasi-β-titanium, characterized by the original microstructure of the core.
These products comply with the first aspect of the present invention.
The second aspect of the invention corresponds to the method of manufacture of such products by the forging method.
Thus, the first task to be solved by the present invention is directed, is to obtain products that are asymmetric with respect to the axis (i.e. non-wire) and having a thickness less than 10 mm (this value is 10 mm defines the concept of "a little thick" and "thin products"used in this description), and are made of alloys β-titanium or quasi-β-titanium. Thus the microstructure of the core of these products is formed by grains, which have a degree is tenutosi (prodolgovatoe) above 4 and the equivalent diameter of 10 to 300 microns.
Specialists in this area known alloys β-titanium or quasi-β-titanium. They have a compact hexagonal structure. They are well characterized, particularly in textbooks USA: ASMH (American Society Material Handbook) and MILH (Military Handbook). Currently, their use is limited to the manufacture of solid forged products or products of great thickness.
Unlike similar products, products made from these alloys in accordance with the invention, are fine products. Their properties are determined by the manufacturing process on the basis of one or more operations of forging. Such products have the original microstructure of the core. The grain of this microstructure are flattened.
They have a degree of elongation above 4. This degree of elongation is traditionally defined as the ratio of the largest dimension to the smallest dimension in the axial plane. Grains have an equivalent diameter of 10 to 300 microns.
Instead of large truncated grain structure is equivalent to (thin) products obtained by mechanical process, in the structure of core products according to the invention there are one-piece tapered lenticular grain.
Products made in accordance with the invention and having the above characteristics represent new products. These new products may be obtained by the method of forging. As explained above, there was a bias against attempts to obtain a fine structure by forging thicker structures with large grains. Unexpectedly it turned out that such subtle patterns have very interesting characteristics.
Products made in accordance with the invention, in an optimal embodiment represent the blades of the compressor of the turbomachine.
The invention is not restricted by these limits. These products can also be screws, namely underwater propellers, fan blades or mixers (which are in the environment, justifying their production of alloys β-titanium or quasi-β-titanium). This list of products is not exhaustive.
According to a particularly preferred variant of the invention (non-limiting) of the product in accordance with the invention is made of Ti17. This alloy is known to specialists in this area, currently used for the manufacture of solid products, namely compressor disks. It has a high yield strength and is also considered to be difficult to forge.
More precisely, we are talking about the alloy:
TA5CD4- metallurgical item
TiAl5Cr2Mo4- on chemical nomenclature.
Unexpectedly within nastojasih the invention of this alloy is Ti 17were forged thin products with a high degree of crimping. These forged products possess improved mechanical characteristics.
Next will be described a method of manufacturing of new products, described above, which corresponds to the second aspect of the invention.
This method of manufacture provides:
- getting enameled workpiece;
transformation, if necessary, this billet in an elongated product of the equivalent diameter of less than 100 mm;
- forging the specified oblong products;
- hardening of the specified oblong wrought products;
- leave the specified forged tempered oblong products.
Subject forging product known pre emulerat. This product represents in the General case, the intermediate product obtained by drawing or forging the source material, which has a larger equivalent diameter (greater thickness). It may be a rod (for example, 25 mm diameter)obtained by drawing the preform. In practice, alloys β-titanium or quasi-β-titanium exist mainly in the form of such blanks (for the manufacture of compressor drives mechanical processing).
This enamel product, that is, in the General case enamel prom is mediate product diameter (equivalent) less than 100 mm, in accordance with the invention transform by forging to finished product thickness less than 10 mm
To obtain such a finished product with optimized properties, the invention provides forging compliance with the following conditions. The forging operation contains at least two steps of hot forging:
the first step of hot forging at a temperature below or above β-transition, in General at temperatures from 700 to 1000°C;
the last stage of hot forging at a temperature above β-transition, in General at temperatures above 880°C.
It is obvious that the specific temperature values depend on the specific alloy β-titanium or quasi-β-titanium.
The degree of compaction (precipitation) at each step of hot forging is chosen equal to 2 or greater (more preferably 2), and speed forging (or speed flatten) ranges from 1 to 1·10-5c-1.
The forging operation may be limited to two phases of the hot forging mentioned above (the second of these stages hot forging must be hot forging at a temperature above β-transition). It may contain additional step of hot forging at a temperature below or above βtransition before the last (third) step of hot forging at a temperature above β-transition. It is possible that it may contain more than Tr is step by step hot forging (the latter must be at a temperature above β -transition), however, the benefits from increasing the number of stages of hot forging are not obvious.
Thus, forging contains in General a two or three stage hot forging carried out in the above conditions.
Known wrought products (forgings) if necessary, re-amaliyat between two consecutive steps of hot forging.
According to an optimal implementation of the stamp support at a temperature of from 100 to 700°C.
After the forging operation traditionally perform the quenching operation (usually directly after forging). This hardening can be performed in a pulsating air, in still air, in an oil bath or directly on the stamp. Optimally it is carried out under such conditions that cause the cooling rate below or equal to the cooling rate during quenching in an oil bath.
Vacation forged tempered products perform optimally at a temperature of from 620 to 750°during the period of time from 3 to 5 hours. These conditions optimize the functions specified characteristics of the finished product. Tempering is carried out in an inert atmosphere (namely, under vacuum or in argon), if the enamel has cracked or peeled off.
According to a particularly preferred variant of the method according to the invention is performed in the following conditions:
- procurement is the second alloy Ti 17(TA5CD4or TiAl5Cr2Mo4);
forging includes a first step of hot forging at a temperature below or equal to 840±10°below β-transition), or at a temperature higher than or equal to 940±10°With (above β-transition), and the second step of hot forging at a temperature of 940±10°With (above β-transition);
- hardening is carried out in the stamp, then in the still air;
- tempering is carried out at a temperature of 630°C for 4 hours
The method provides for obtaining the products described in the first part of this description, and this product can be a shovel.
The manufacture of such blades are described in more detail below as an example.
List of figures
Figures 1 and 2 are shown in different scales of the original microstructure of the core of such blades.
Information confirming the possibility of carrying out the invention
Figure 1 shows the cut in three directions: cross section in the plane And a longitudinal section in the plane and In the frontal cross-section in the plane C. the Magnification is 20x. Figure 1 is clearly visible to the lenticular shape of the grains, strongly tapered in transverse and longitudinal directions, and having a broad surface in the frontal cross section.
Figure 2 shows a cut in the scale h. Position 1 indicated they are pressed the grain, position 2 - recrystallized grains. The boundaries between the grains are very fine and have a complex weave.
Example: Manufacture of blades of Ti17method of forging.
Used the method comprises the following successive stages:
- drawing rod (diameter <100 mm) to obtain a billet with a diameter of 27 mm and a length of 240 mm;
radial flattening volokonnogo rod for forming blades and base;
- heat the press to 200°C;
- speed impact (screw press): 10-4with-1;
|the first step of hot forging:||enamel preparation, sustained for 45 min at 940°With (hot forging above β-transition), flatten to a thickness of from 13 to 8 mm;|
|- the second step of hot forging:||conditions similar to the first step of hot forging; re-flattening enables the creation of products with thickness from 9 to 1 mm|
- cooling in the stamp, then on the table in the still air;
- leave directly after forging at a temperature of 880°C for 4 hours
The result is a blade with a microstructure of the core, which corresponds to the microstructure presented on the attached drawings.
1. The product with thickness less than 10 mm, asymmetry the Noah axis, made of alloy β-titanium or quasi-β-titanium and having a microstructure of the core, formed of whole grains with the degree of elongation above 4 and an equivalent diameter of 10 to 300 microns.
2. The product according to claim 1, characterized in that it is adapted for receipt by the forging method.
3. The product according to claim 1 or 2, characterized in that it is a blade of the compressor of the turbomachine.
4. Product according to any one of claims 1 to 3, characterized in that it is made from a TiAl alloy5Cr2Mo4(Ti17or TA5CD4).
5. A method of manufacturing a product according to any one of claims 1 to 4, providing
getting enameled workpiece;
conversion if necessary, this billet in an elongated product of the equivalent diameter of less than 100 mm;
forging specified oblong products;
quenching specified oblong wrought products;
leave the specified forged tempered oblong products.
6. The method according to claim 5, characterized in that the forging includes at least two steps of hot forging: the first stage hot forging at a temperature below or above β-transition and final step of hot forging at a temperature above β-transition, the degree of compaction at each step of hot forging is selected equal to or greater than 2, and sorostitute range from 1 to 1· 10-5with-1.
7. The method according to claim 6, characterized in that the forging involves three steps of hot forging: the first and second stages at a temperature independently select below or above β-transition, and the third stage at a temperature above β-transition.
8. The method according to claim 6 or 7, characterized in that it provides for the operation of re-enamelling of the product between two phases of the hot forging.
9. The method according to any of pp.5-8, characterized in that the stamp support at a temperature of from 100 to 700°C.
10. The method according to any of pp.5-9, characterized in that the specified tempering is performed in conditions that cause a cooling rate lower than or equal to the cooling rate during quenching in an oil bath.
11. The method according to any of pp.5-10, characterized in that the tempering performed at a temperature of from 620 to 750°during the period of time from 3 to 5 hours
12. The method according to any of pp.5-11, characterized in that
the workpiece is obtained from alloy TiAl5Cr2Mo4(Ti17or TA5CD4);
forging includes a first step of hot forging at a temperature below or equal to 840±10°or at temperatures less than or equal to 940±10°and a second step of hot forging at a temperature of 940±10°C;
quenching is carried out in the stamp, and then in the still air;
vacation spend pritemperature 630° With over 4 hours
FIELD: nuclear engineering.
SUBSTANCE: zirconium-based alloy for manufacturing tubes used in nuclear reactors includes 2.5-2.8% Nb and 0.05-0.13% Fe and another alloy includes 0.9-1.2% Nb, 1.1-1.42% Sn, 0.3-0.47% Fe, and 0.05-0.12% O. Method for manufacturing seamless tubes is directed to increase resistance of tubes to retarded hydride creaking, high destruction viscosity, length uniformity of mechanical properties: corrosion resistance, strength, and creep rate. Specifically, manufactured tubes are characterized by retarded hydride creaking rate less than 6x10-8 m/s at 250°C, threshold coefficient of stress intensity above 10 MPavm at 250°C, viscous destruction resistance, dJ/da, above 250 MPa at 250°C, and stretching strength above 480 MPa at 300°C.
EFFECT: improved performance characteristics of tubes.
16 cl, 1 tbl, 6 ex
FIELD: plastic working of materials, namely apparatuses for strengthening material at working process.
SUBSTANCE: apparatus for working sheet blanks by equal-duct angular pressing includes housing in which roll with П-shaped groove is mounted; annular sector insert joined with roll groove and secured to block. Said insert has contact surface arranged eccentrically relative to contact surface of roll and it forms stationary wall of working duct for receiving blank. Said block is joined with housing by means of wedge clamp and it is mounted in axle with possibility of rotation. Stop is mounted in recess of housing for forming lower wall of outlet duct. Apparatus may perform translation motion and its housing is rigidly secured to strut coupled with frame. Apparatus includes platform for receiving blank after pressing it out in motion direction of apparatus. Roll having annular bandages along its ends is mounted with possibility of rotation. Roll, П-shaped groove, annular sector insert and block have such geometry sizes that provide pressing of blank. Blank is pressed out in direction opposite relative to motion direction of apparatus. In order to enhance efficiency of working roll is in the form of vibrating roll.
EFFECT: possibility for working large-size sheet blanks, improved manufacturing effectiveness and efficiency of working of sheet blanks.
3 cl, 1 dwg
FIELD: plastic working of materials.
SUBSTANCE: method comprises steps of deforming blank in vertical and horizontal ducts while moving blank in horizontal duct at applying counter-pressure to it by performing percussion action upon blank in direction opposite relative to blank motion direction. Blank is also subjected to rotation in arbitrary direction. Percussion-rotation actions upon blank in horizontal duct are cyclically repeated. Counter pressure effort and frequency of percussion-rotation action upon blank in horizontal duct are also cyclically repeated.
EFFECT: improved physical-mechanical properties of materials, enhanced quality of blanks, simplified working process.
FIELD: metallurgy; mechanical engineering; aircraft engine manufacture; medicine.
SUBSTANCE: proposed method includes intensive plastic deformation of blank in crossing vertical and horizontal channels at temperature of 600°C at stored logarithmic degree of deformation no less than 2. Heat treatment performed before intensive plastic deformation includes hardening from temperature of polymorphous transformation of minus 10°C in water and high-temperature aging at temperature of 675-700°C continued for 4 hours at cooling in air; after intensive plastic deformation, blank is subjected to extrusion performed in several passes at temperature of 300°C and drawing coefficient no less than 1.2.
EFFECT: improved strength characteristics (ultimate strength, yield point, fatigue range); enhanced homogeneity at retained satisfactory ductility.
1 tbl, 1 ex
FIELD: metallurgy; production of superconducting wires operating at temperature of liquid helium in magnetic systems of charged-particle accelerators.
SUBSTANCE: proposed method includes homogenizing annealing of ingot within temperature interval of from 1200 to 1350°C and application of protective copper coat on ingot. Then, ingot is heated to temperature of 800-900°C and is subjected to extrusion deformation for obtaining first billet which is subjected to machining followed by application of protective copper coat. First billet is heated at temperature of 800-900°C and is subjected to extrusion deformation for obtaining second billet which is also subjected to machining. Then, the following operations are performed: re-crystallization annealing at temperature of from 950 to 1250°C, cold rolling to preset size of billet and re-crystallization annealing at temperature of from 950 to 1250°C. Billets thus produced possess property for further deformation at total drawing of up to 9·108 for production of superconductors.
EFFECT: enhanced efficiency; avoidance of undesirable diffusion processes.
7 cl, 3 ex
FIELD: mechanical engineering; aircraft engine manufacture and medicine.
SUBSTANCE: proposed method consists in thermo-mechanical treatment accompanied by change in mechanical properties of material. Proposed method includes intensive plastic deformation of blank in crossing vertical and horizontal channels at temperature of 600°C and stored logarithmic degree of deformation no less than 2. After intensive plastic deformation in crossing channels, blank is subjected to extrusion by several passes at temperature of 300°C and drawing coefficient no less than 1,2.
EFFECT: enhanced strength characteristics of titanium alloys (ultimate strength, yield point, fatigue range) at retained satisfactory ductility.
1 tbl, 1 ex
FIELD: mechanical engineering; aircraft engine manufacture and medicine.
SUBSTANCE: proposed method is accompanied by change in physico-mechanical properties of metal. Proposed method of production of ultra-fine-grain titanium blanks includes intensive plastic deformation of blanks in crossing vertical and horizontal channels at temperature of 500-250°C and thermo-mechanical treatment. Thermo-mechanical treatment including annealing and deformation is performed before intensive plastic deformation at stored logarithmic degree of deformation no less than 4.5; annealing is carried out at temperature not above temperature of polymorphous transformation minus 200°C; thermo-mechanical treatment is started at annealing temperature which is reduced in stepwise manner to temperature of intensive plastic deformation. Ultra-fine-grain structure is formed at lesser number of technological passes.
EFFECT: improved strength characteristics; reduced labor consumption; enhanced efficiency.
2 cl, 1 tbl, 1 ex
FIELD: metallurgy; methods of production of extra-thin tubes from zirconium alloys and vacuum annealing plants.
SUBSTANCE: proposed method includes hot deformation of billets, preliminary cold deformation of billets at vacuum annealing, cold rolling of tubes at deformation at last stage at degree of 32-69% followed by final vacuum annealing performed in vertical position at temperature of alpha-region of zirconium continued for 2-3 h. At annealing, tubes are heated at rate not exceeding 55°C/min; their cooling is performed at rate not exceeding 30°C/min. Annealing device has housing hermetically closed with cover and provided with electric heaters, muffle with loading unit having seats for tubes and retainer for securing them in required position, suspension and system for evacuation of muffle and housing cavities. Loading unit is made in form of identical disks secured on central rod in tiers; disks have holes for forming the seat for vertical position of tubes; upper end of rod is articulated with suspension mounted in upper part of muffle.
EFFECT: reduction of maximum deviation of external diameter from rectilinearity of tubes.
5 cl, 3 dwg, 1 tbl
FIELD: plastic working of metals, in particular, production of laminated materials.
SUBSTANCE: method involves providing blank of low-alloy two-component alloy; deforming blank at reduction extent of at least 80% and extension coefficient of at least 5; upon termination of deformation procedure, subjecting blank to thermal processing in direction oriented from its larger to smaller section and saturating with hydrogen at each stage of manufacturing laminated material. Blank used is cable blank with magnesian insulation.
EFFECT: increased deformability, improved corrosion and fatigue resistance of materials employed in various branches of industry.
5 cl, 4 dwg, 3 ex
FIELD: plastic working of metals, in particular, production of laminated material from metal alloy, for example Zr-Nb alloy, for producing of cable sheathing for thermal couple.
SUBSTANCE: method involves providing plastic deformation of blank made from zirconium alloy in at least two directions, with deformation extent in one direction exceeding deformation extent in other direction by at least three times, and total algebraic value of deformation extent in all directions making at least 250%. After deformation, blank of zirconium alloy may be additionally exposed to annealing in vacuum furnace at temperature of up to 600 C.
EFFECT: increased efficiency in producing of three-layer material with increased deformation capability and high corrosion and fatigue destruction resistance.
2 cl, 5 dwg, 1 ex
FIELD: special-purpose electrical metallurgy; production of high-quality ingots from high-temperature alloys on base on titanium alloyed by low-melting elements, for example aluminum, tin and silicon.
SUBSTANCE: burden of low-melting alloying elements is charged into water-cooled copper crucible with skull made from the same alloy in its bottom part; consumable electrode made from parent metal or from alloy is molten into crucible and is poured into ingot mold. Low-melting alloying element charge is loaded on larger base of riser of casting of previous melt made in form of truncated cone whose lesser base is mounted on skull of crucible bottom part; diameter of larger base of riser is preset depending on limits of ratio 0.8≤(dr/tcr-4)≤0.9, where dr is diameter of riser larger base of casting of previous melt, cm; dcr is diameter of crucible bottom, cm. Ingots produced by this method may be used for plastic metalworking of metals and alloys.
EFFECT: stable high quality of ingots due to chemical homogeneity; low labor input.
2 tbl, 2 ex
SUBSTANCE: invention relates to titanium-base alloys. Invention proposes titanium-base alloy containing the following components, wt.-%: aluminum, 4.7-6.3; niobium, 0.4-0.8; molybdenum, 1.5-2.5; zirconium, 0.5-1.5; carbon, 0.06-0.12; oxygen, 0.08-0.14, and titanium, the balance, wherein the total content of oxygen and carbon must be 0.22 or less. Alloy is designated for using in medicine and other branches of industry. Alloy can be used in making different articles and constructions, among them, for medicinal equipment, tools and articles used in traumatology and orthopedics. Invention provides the development of alloy showing the enhanced plasticity and strength.
EFFECT: improved and valuable properties of alloy.
FIELD: metallurgy; titanium alloys used in media where risk of breakage due to hydrogen absorption is present.
SUBSTANCE: proposed titanium-alloy material contains 0.5-3.0 mass-% of aluminum at thickness of layer of 0.10-30 mcm with increased content of Al which is formed in solid part of material; content of Al in this layer exceed content of Al in solid part of material by 0.3 mass-% and more and content of Al in layer ranges from 0.8 to 25 mass-%. This material may be used in media where risk of embrittlement due to hydrogen absorption is present. After cold treatment, material possesses the same properties as pure titanium.
EFFECT: enhanced efficiency.
5 cl, 3 tbl, 1 ex
FIELD: non-ferrous metallurgy, namely manufacture of modern titanium base alloys suitable for universal use.
SUBSTANCE: alloy contains next components, mass. %: aluminum, 4.0 - 6.0; vanadium, 4.5 - 6.0; molybdenum, 4,5 - 6.0; chrome, 2.0 - 3.6; iron. 0.2 - 0.5; zirconium, 0.1 - less than 0.7; oxygen, no more than 0.2; nitrogen, no more than 0.05; titanium, the balance. Such alloy may be used for producing wide assortment of articles such as large-size formed and forged products, semi-finished products with small cross section area such as rods, plates with thickness up to 75 mm widely used in aircraft manufacture, possibly for making mounting parts.
EFFECT: titanium alloy with high strength and improved ductile properties.
FIELD: metallurgy; high-strength alpha-beta alloys.
SUBSTANCE: Specification gives versions of titanium-based alpha-beta alloys. The proposed alloy contains the following components: aluminum, 4.5-5.5; vanadium, 3.0-5.0; molybdenum, 0.3-1.8; iron, 0.2-0.8; oxygen, 0.12-0.25; by-elements and admixtures, lesser than 0.1 each; total amount of by-elements and admixtures is lesser than 0.5; the remainder being titanium.
EFFECT: high strength of alloy, good workability and ballistic properties.
4 cl, 5 tbl, 3 ex
SUBSTANCE: invention relates to titanium-base alloys used in making high-strength and high-efficient articles. Titanium-base alloy consists of aluminum, vanadium, molybdenum, iron and oxygen. Components of alloy are taken in the following ratio, wt.-%: aluminum, 3.5-4.4; vanadium, 2.0-4.0; molybdenum, 0.1-0.8; iron, max 0.4; oxygen, max 0.25, and titanium, the balance. Invention provides the development of universal alloy for large-sized forged pieces and stamps, thin-sheet roll and foil possessing the necessary strength and plastic indices and structure.
EFFECT: improved and valuable properties of alloy.
FIELD: metallurgy, in particular, titanium-based materials resistant to change of color.
SUBSTANCE: construction material of pure titanium contains, wt%: Fe 0.08 or less; Nb 0.02 or less; Co 0.02 or less, and is provided with surface oxide film having thickness of 170Å or less. Method involves producing material from pure titanium; etching and heating to temperature X( C) within the range of from 130 C to 280 C for time T (min) satisfying condition of T≥239408xX-2,3237.
EFFECT: increased resistance to change of color for prolonged time as compared to traditional materials.
3 cl, 2 dwg, 4 tbl, 3 ex
FIELD: medicine; instrument-making industry; radio industry; production of materials with a memory effect of the form.
SUBSTANCE: the invention is pertaining to the materials with a memory effect of the form and with the modified surface, which may be used as implants in medicine and as the temperature sensors, thermo-sensitive and executive elements and designs in instrument-making industry, the radio industry. The offered material consists of a base made out of a titanium nickelide of the following composition (in at. %): titanium - 49-51, nickel - the rest, and the surface layer modified by alloying elements. The modified surface layer is formed by irradiation with a low-energy high-current electronic beam and has a depth of 1000-2500 nanometers and the dimensions of the crystal grains of no more than 30 nanometers. In the capacity of the alloying elements it contains oxygen and carbon at the following ratio of components (in at. %): oxygen - 10-20, carbon - 10-15, titanium - 40-50, nickel - the rest. The technical result of the invention is production of the materials with an effect of memory of the form and a high degree capability of the form restoration both at a low and high deforming loadings.
EFFECT: the invention ensures production of the materials with an effect of memory of the form and a high degree capability of the form restoration both at a low and high deforming loadings.
1 tbl, 1 ex
FIELD: nonferrous metallurgy; aircraft industry; mechanical engineering; development of alloys on the basis of titanium.
SUBSTANCE: the invention is pertaining to the field of nonferrous metallurgy, in particular, to development of alloys on the base of titanium, working at the heightened temperatures. It may be used in an aircraft industry for manufacture of components, for example, disks, vanes, rings, and also in mechanical engineering. The invention presents an alloy based on titanium and a hardware product produced out of it. The alloy contains aluminum, zirconium, stannum, niobium, a molybdenum, silicon, carbon and oxygen. At that it in addition contains tungsten and iron, at the following ratio of components (in mass %): aluminum 5.8 - 6.6, zirconium 2.0 - 4.0, stannum - 2.5 - 4.5, niobium - 0.8-2.5, molybdenum - 0.8- 1.5, silicon - 0.25-0.45, carbon - 0.05-0.1, oxygen -0.05-0.12, tungsten - 0.35-0.8, iron - 0.06-0.13, titanium - the rest. The technical result is a development of an alloy having the lower weight at the given short-time strength and a specific low-cycle fatigue, that increases an operational life and reliability of the components of the hot tract of aero-engines.
EFFECT: the invention ensures development of an alloy with the lower weight at the given short-time strength and a specific low-cycle fatigue with increased operational life and reliability.
2 cl, 2 tbl, 3 ex
FIELD: non-ferrous metallurgy; methods of titanium alloy bricks production.
SUBSTANCE: the invention is pertaining to the field of non-ferrous metallurgy, in particular, to the brick made out of α+β titanium alloy and to a method of its manufacture. The offered brick consists of the following components (in mass %): aluminum - 4-5, vanadium - 2.5-3.5, iron - 1.5-2.5, molybdenum - 1.5-2.5, titanium - the rest. At that the alloy out of which the brick is manufactured, contains - 10-90 volumetric % of the primary α-phase. The average grain size of the primary α-phase makes 10 microns or less in a cross-section plain parallel to the brick rolling direction. Elongation of grain of the primary α -phase is the four-fold or less. The offered method of manufacture of the given brick includes a stage of a hot rolling. At that before the stage of the hot rolling conduct a stage of the alloy heating at the surfaces temperature (Tβ-150)- Tβ°C. During realization of the stage of the hot rolling the surface temperature is kept within the range of (Tβ-300)-( Tβ -50)°C, and the final surface temperature, that is a surface temperature directly after the last rolling, makes (Tβ-300)-( Tβ-100)°C, where Tβ is a temperature of α/β-transition. The technical result of the invention is formation of a brick out of the high-strength titanium alloy having a super pliability, excellent fatigue characteristics and moldability.
EFFECT: the invention ensures production of a brick out of the high-strength titanium alloy having a super pliability, excellent fatigue characteristics and moldability.
7 cl, 7 dwg, 21 tbl, 2 ex
FIELD: production of items from high-doped high-temperature wrought nickel alloys for disks of gas-turbine engines.
SUBSTANCE: proposed method includes vacuum induction melting for obtaining ingot for deformation. At least one cycle of pre-extrusion is performed which is followed by recrystallization annealing. Extrusion of blank is performed in die by repeated forcing of blank from cylindrical to taper part of die at temperature below Tc.d.γ' by 55-95C. Die is heated to temperature not below Tc.d.γ' -250C and not above the blank heating temperature. Rate of deformation , where Tc.d.γ' is temperature of complete dissolving of γ' phase. During each subsequent stage of forcing-out the blank, direction of forcing out is reversed as compared with previous stage. Prior to final deformation, blank is subjected to intermediate annealing. Items made from high-temperature nickel alloy have homogeneous structure in complex stampings and stable level of properties ensuring reduction of extrusion force and final deformation.
EFFECT: enhanced efficiency; increased factor of utilization of metal.
7 cl, 1 dwg, 3 tbl, 6 ex