The method of machining of metals and alloys

 

(57) Abstract:

Usage: the invention relates to the field of metal forming and can be used to produce blanks with regulated physico-mechanical properties, including through the formation of fine patterns. The method is designed to handle workpieces in the form of rods, bars and other predominantly of long workpieces. Essence: in the method of machining of metals and alloys, including deformation, at least a section of the workpiece through various schemes, including leading to reduction of its cross section, in which you take the billet in the form mainly of lengthy rod, the reduction performed by the tool, with the possibility of relative displacements along and across the axis of the workpiece and relative to the running surface, for example, roller, using at least two supports, which include procurement, and the desired degree of deformation provide, using at least one of the schemes deformation, sold in torsion, upsetting or stretching through a tool, for example, the supports are made with vozmozhnosti, required to achieve a given structure and physico-mechanical properties of the workpiece. The invention provides for the creation of a cost-effective method of deformation processing of workpieces in the form of long rods of large diameter, providing them regulated patterns, including microcrystalline and specified physical and mechanical properties. 23 C.p. f-crystals, 1 tab., 6 Il.

The invention relates to the field of metal forming and can be used to produce blanks with regulated physico-mechanical properties, including, due to the formation of fine patterns. The method is designed to handle workpieces in the form of rods, bars and other, mostly long, blanks.

It is known that many physical and mechanical properties such as strength and ductility depend on the structure of materials. Therefore, with the change in the structural state of the resulting plastic deformation of the material, they also change. In particular, the strengthening of the material usually results in the formation in it cell or subgrain structure.

Most significantly physico-mechanical properties of materials snisky temperatures have significantly higher strength characteristics, than conventional coarse-grained, and at elevated temperatures low voltage currents and high plasticity or superplasticity. However, for the formation of the microcrystalline structure required a radical deformation processing material with high degrees of deformation than for any other fragmented structure, such as subgrain.

Known methods for deformation processing of workpieces, such as equal channel angular pressing [1] and torsion under pressure [2], used for receiving the blanks regulated physico-mechanical properties, including by obtaining them microcrystalline structure. These methods allow to obtain only a small mass and size of fine-grained semi-finished products and are of high complexity and energy consumption.

A known method of deformation machining of metals and alloys, which are strain by repeated reduction and subsequent increase of its cross-section, respectively, of the extruded and draft container [3]. This method allows you to get small bars of soft materials with improved the processing of the blanks according to the prototype method requires a large enough energy to overcome the forces of friction on the contact surfaces of the workpiece and hydrostatic pressure during extrusion pressurized. Therefore, this method cannot be applied to obtain large-grained semi-finished products, in particular, long 5-6 meters bars with diameter ranging from 150-200 mm from difficult-to-deform alloys. In this case, would require enormous power of the press, developmental efforts in the tens of thousands of tons, as well as the appropriate tool. Usually the rods with a microcrystalline structure with a grain size of 3-8 μm, a small 30-40 mm in diameter, get a multistage forging or rolling of the billet (ingot) with the initial diameter of 400 mm or more.

The objective of the invention is the creation of a cost-effective method of deformation processing of workpieces in the form of long rods of large diameter, providing them regulated patterns, including microcrystalline and specified physical and mechanical properties.

This problem is solved in the method of machining of metals and alloys, including deformation of at least a section of the workpiece through various schemes, including leading to reduction of its cross section, in which you take the billet in the form mainly of lengthy rod, the reduction perform instrume surface, for example, a roller, using at least two supports, which include procurement, and the desired degree of deformation provide, using at least one of the schemes deformation sold torsional, draft or extension, by means of an instrument such as the mentioned supports are made with the possibility of impacts on the procurement of the relevant schemes deformation forces, when the temperature of the deformable section, required to achieve a given structure and physico-mechanical properties of the workpiece.

In addition, it is recommended that:

in the case of a relative break the surface of the rod more than one roller to use a single prop;

the reduction of area to do with application to the workpiece tensile axial forces by means of supports with clamps;

reduction of site run by transverse rolling of billet rollers;

reducing run by the longitudinal-transverse rolling of billet rollers;

the reduction be achieved by rolling the billet rollers, the axis of rotation of which form the skew angles with the axis of the workpiece;

the reduction of the workpiece to produce three rollers, raspada not exceeding three minimum rod diameters in the reduced cross-section;

the reduction of area to perform under the action of compression along the axis of the workpiece effort;

torsion of the workpiece to produce by means of bearings and rollers;

to produce reverse twist;

deformation plot to make by using a shape of the roller, the profile of which is formed with average maximum dimensions of a part, which is converted from its ends, the intermediate part and the next, beginning with the smallest cross-sectional dimension of the intermediate section, two end pieces;

draft procurement section to perform after lateral movement of the rollers in the direction from the axis of the workpiece by an amount not to exceed the absolute value of the transverse deformation of this area when it is reducing;

draft procurement section to produce after the longitudinal-transverse movement of the rollers relative to the axis of the workpiece;

draft procurement section to perform simultaneously with the rolling surface of the rollers with respect to the conditions:

u> i<e,

whereithe stress intensity rainfall area defined with the resistance to deformation provided by the rollers during running; u- voltage, causing the loss of stability of nidiformis the information to perform a continuously-consistently along the entire length of the workpiece;

part of the preparations from single-phase alloys deform with the true degree of deformation of at least 3, including in combination with the degree of not less than 1.4, and the deformation to be carried out with speed 101- 10-2with-1at the temperature of (0.3 to 0.5)TPLwhere TPLthe melting point of the workpiece material;

part of the preparations from multiphase alloys deform with the true degree of deformation of at least 2, including in combination with the degree of not less than 1.4, and the deformation is carried out at speeds of 10-1- 10-4with-1when the temperature (from 0.5 to 0.85)TPLwhere TPLthe melting point of the workpiece material;

part of the billet of titanium alloy with a lamellar structure and deform with the true degree at least 3 reduction, torsion simultaneously running rollers, and to settle with the simultaneous running rollers, and torsion combined with reducing and subsidence, and deformation of the implement at a temperature of 700 - Tp. pand strain rates of 10-1- 10-4with-1, Tp. pthe temperature of polymorphic transformation of material from the workpiece;

part of the billet of titanium alloy with a lamellar structure and deform the modern running rollers, moreover, the deformation to be carried out at a temperature of 700 - Tp. pand strain rates of 10-1- 10-4with-1, Tp. pthe temperature of polymorphic transformation of material from the workpiece;

reduction plots billet of titanium alloy with a lamellar structure to conduct to reduce the cross-sectional area not less than 1.1 times at temperature Tp. pto Tp. p+ (10 to 50), then plot the cooling speed of not less than 1o/s, and the torsion and a draught of conduct with running rollers simultaneously at a temperature not exceeding 700 - Tp. pwith strain rates of 10-1- 10-4with-1where Tp. pthe temperature of polymorphic transformation of material from the workpiece;

the parts of the blank of heat-resistant Nickel alloys deformed at a temperature not higher than the temperature of complete dissolution of the intermetallic phase;

the deformation at each site to produce up until a definite increment of deformation rate on 10 - 20% under prescribed conditions of temperature and strain rate will not change in the voltage of the current -fmore than 5 - 10%;

the deformation at each site to produce a given temperature and strain rate up until the jump m = (logN1-logN2)/(log1-log2) to values in the range of 0.3 - 0.8;

where N1N2- load (torque, tension, compression or tension when the corresponding type strain), acting on the workpiece before and after the speed change from the value of1. to the value of2;

The explanation of the invention. In accordance with the way everyone treated area is subjected to geometric loss of strength due to the reduction of its cross section roller tool.

The requested admission, is not only the intense deformation of the roller tool material on this site, including the Central area, but the conditions for its further deformation processing. Deformation is not allocated, not scattered across the workpiece and concentrated, localized in a specially allocated for this reduced area. Therefore, this is where we reach the required structural changes. It also promotes the use of different schemes of deformation of the plot, including the deformation of the rollers (rolling), tension, compression, shear (torsion), as well as the possibility of varying the geometrical dimensions of the plot, ve the CA at a temperature required to achieve a given structure and mechanical properties, can also be regarded as a factor leading to localization of deformation due to thermal softening of the material of the site. However, what is more, the heating temperature of the site and the possibility of its change dramatically affect the formation of one or other regulated entities, such as microcrystalline, which is usually produced by passing the initial or dynamic recrystallization of the deformed material. In accordance with the results of many studies in recent years, the formation of such patterns can occur in a wide temperature range. The choice of a specific heating temperature of part or all of the workpiece depends on the material and type of microstructure, which must be formed in the workpiece during processing of the proposed method. In particular, to obtain a fine-grained structure in the pure single-phase metals and their alloys deformed at lower temperatures than complex-alloyed multiphase metallic materials.

Given, i.e., the required deformation provide, using at least (except reduction roller) is one of the CX the actors - the desired deformation study and generated by this structure, the workpiece material, the initial and final size and shape of the workpiece. If you are processing a workpiece with a relatively small cross-section, a sufficient one. For example, torsion for grinding grains to a greater extent in the surface layer of the rod compared to the center, and also in those cases where no alteration of the cross-section of the workpiece. For the formation of more uniform cross-section structures use stretching or draft given the fact that the sediment allows you to receive the rod with cross-sectional sizes, loved ones or big, and stretching less original. It should be noted that the torsion as a factor in the formation of a uniform structure in the cross section, can be used without stretching or precipitation, if the deformation is performed in a temperature-speed conditions of superplasticity (SPD). In this case, first there is the grinding of the grains in the surface layers, and then, as a further twist, and in the internal region of the workpiece, in this case, due to the known characteristics SPD, significant changes in the structure in the outer layers will not occur. In sformirowal large cross-section is rational to use a larger number of schemes deformation. Thus they can be used sequentially or simultaneously. The latter provides a significant reduction of the axial forces in the deformation area. In addition, the same plot can be repeated using the previous combination schemes deformation or different combination schemes and modes, for example, reducing the heating temperature can in some cases be obtained after the second treatment more fine-grained structure than after the first treatment. In General, the combination of different schemes allows a wide range to vary the degree (amount) accumulated strain in the treated area of the workpiece and thus to exert sufficient for the formation of regulated physico-mechanical properties of deformation study of rod material.

Along with the above choice of a particular scheme and their quantities for the formation of the regulated structure is also due to the deformation characteristics of the material. For materials prone to localization of deformation, in particular for titanium alloys, it is necessary to process the workpiece, using several schemes simultaneously in order to increase the homogeneity of the deformation. Similar treatment is STI deformation increases deformability of the workpiece as a whole. For materials with a wide range of possible slip systems, in particular for single-phase alloys based on Nickel, can be processed using at least one of the schemes.

The efficiency of the proposed method is determined by the energy and material consumption.

To convert coarse-grained structures in fine-grained needed in each sufficiently small area of the workpiece to accumulate deformation of large magnitude. Such schemes as extrusion and sediment billet in the container used in the prototype, especially when multiple applications are required, ensure the accumulation of the material deformation. However, it was noted above that these schemes are very energy intensive. The high cost of energy is also needed if a comprehensive forging billets, which are often used to obtain them in a homogeneous fine-grained structure. First, she takes on multiple heat treatment of the workpiece, because for one the heat is almost impossible to achieve uniform grinding of grains. Secondly, this forging is repeated sediment blanks with the change of direction of compression, and at upsetting deformation is distributed unevenly: there are areas of intense deformation, is Otomo that in areas where the deformation was insufficient, are the processes of return. Therefore, in such areas need to expend energy intensive accumulation of structural defects required for recrystallization.

In the proposed method, the zone of deformation is localized, so it is much faster than at upsetting and forging the entire workpiece is achieved required for recrystallization of the dislocation density. In addition, it reduces the cost of energy to overcome the resistance of friction, because the sliding friction occurring during extrusion and upsetting used in the prototype, is replaced by rolling friction during running rollers.

Compared to the forging material saving in the proposed method provides a reduction in the number of operations needed to obtain the regulated structure to one. Thus, excluded shop metal loss during heating, removing defects, scale, etc. furthermore, the method allows to obtain, if you do not want, the workpiece without any or substantial reduction of its diameter in relation to the original. In this regard, the processing may be affected by prutenia bars of large diameter with a large chemical, phase and the grain structure heterogeneity.

The proposed method does not require the use of metal tooling and powerful presses. Below it is shown that the force required for precipitation, the proposed method is substantially less than with conventional upsetting and even more so when the sediment in the container, i.e., essentially stamping.

Along with the above savings of material contributes to the possibility of using the method for correcting the original form of rod - correct curvature along the length, ovality, cut and get through the running rollers high form accuracy and surface finish.

The proposed method provides the blanks previously not achievable effect - the possibility of obtaining long rods of large diameter physico-mechanical properties corresponding to the fine-grained state of the material. If necessary, you can produce products with regulated changes in its properties over the cross section and length, for example one part of the shaft to impart improved heat resistance by forming a relatively coarse-grained structure, and the other part high strength by grinding grains. In addition to the above, the proposed measures or practically to keep the original dimensions of the workpiece.

Recommended methods of implementation method to optimize the conditions of its implementation, including taking into account characteristics of the workpiece material.

Thus, the increase of the ductility and deformability procurement contributes to the following:

use curved roller and the application to the workpiece tensile axial force when the reduction of area by preventing the formation of ridges of displaced upon introduction of the roller material;

the execution of the reduction of area by three rollers arranged relative to each other through the 120ocreating a lateral hydrostatic afflux;

the use of reverse torsion, due to changing the direction of deformation and increasing the number of possible slip systems;

the reduction of the area under the action of compressive forces acting along the axis of the workpiece and sediment blanks on the site, performed simultaneously with the rolling surface of the rollers, which increases the softness of the schema of the stress state.

Increase the resistance of the workpiece during processing techniques such as the choice of the length of each treated area not to exceed three minimum rod diameters in the reduced section, the sediment material is ing the magnitude of the transverse deformation of this area when it is reduced, as also previously indicated acceptance of sediment blanks on the site simultaneously with the rolling surface of the rollers with respect to the conditions:u> i<e.

The methods according to which it should:

conduct a draft of the workpiece at the site after the longitudinal-transverse movement of the rollers relative to the axis of the workpiece;

deformation to run continuously-processed consistently across the length of the workpiece, reducing run by running blanks with the movement of three rollers arranged relative to each other with an interval of 120oand with crossed rollers relative to the axis of the workpiece own axes of rotation - increase the productivity of the process.

Receiving, in which case the relative break the surface of the rod by more than one roller use one tether allows you to handle end portion of the rod, i.e., saves material and improves the yield.

In some cases it is advisable to perform the processing of individual pieces. For example, areas at a distance not exceeding three diameters of the workpiece. After the partition of such a measuring rod blanks by means of the treated areas will be art is art coarse-grained. After precipitation of such blanks in the conditions of the SPD out of the washer with a homogeneous structure, without stagnant zones.

The methods by which the parts of the workpiece is heated to a predetermined temperature and treated with a given degree - P. and strain rates, are recommended for fine-grained structure taking into account the nature of the materials. The specific numerical value of the power accumulated in the material deformation varies depending on processing tasks. To obtain a material with low-angle grain (subgrains) is usually sufficient deformation within e = 0.3 to 0.6, where f is the true degree of deformation. When grinding grains up to level 10 μm, you need to e 2, and for submicrocrystalline and nanostructures desired deformation, the true value of which reaches e 5, i.e. the higher the degree of deformation, the smaller the generated structure. The proposed method allows to effectively recruit such deformation, due to the diversity and variation of applied schemes.

For workpieces of single-phase materials because of the growth of grains are recommended lower temperature than for multiphase materials.

In multiphase alloys structure more stable, so the top is tons of grains phases, and the lower 0.5 TPL- diffusive activity and plasticity of the material. For billets of titanium alloys such temperatures are 700oC and (Tp. p- 150o)C, and heat-resistant Nickel of 0.5 TPLand temperature of dissolution hardening intermetallic phase.

Strain rate recommended appropriate conditions SPD, because in such conditions, structural changes are most intense.

The completeness of the transformation of the original structure in crystalline, especially in titanium alloys facilitates the simultaneous use of schemes deformation method, in particular the implementation of the torsion test and/or precipitation.

Effective for rods made of titanium alloy with a large cross-section is the processing, which is first made by heating the billet to a temperature Tp. p- Tp. p+ (10 - 50o)C, then reducing reduce the cross-sectional area of 1.5 - 2 times, then the plot is cooled (quenched) with a minimum speed of 1o/s, and the torsion draught with running rollers carried out at a temperature not above Tp. p. This provides an increase in the hardenability of the alloy in the reduced section obrazovanii temperature below the temperature of polymorphic transformation.

The method allows the use of monitoring mechanical parameters such as coefficient of velocity sensitivity voltage current - m, the magnitude of the moment, etc., to assess the degree of transformation of the original structure in fine-grained. If m is 0.3 or more in increments of deformation or specific efforts did not change significantly, it means that fundamental structural changes have been completed, the workpiece is practically formed of fine-grained structure.

The method is illustrated with the help of illustrations, which provides:

in Fig. 1 is a structural diagram of a device for implementing the method;

in Fig. 2 - flowchart of processing of the workpiece at various stages, designated as 2A, 2B, 2C, 2D, 2E, 2F, 2H;

in Fig. 3 - a device for modeling the way;

in Fig. 4 - microstructure of a sample of titanium alloy DT8 in the initial state;

in Fig. 5 - microstructure of a sample of titanium alloy DT8 after treatment by the proposed method;

in Fig. 6 - macrostructure billet of titanium alloy DT8 after treatment by the proposed method.

Examples of implementation of the method

In Fig. 1 shows a structural diagram of an apparatus for implementing 11, for lateral movement of the rollers, the carriage 12 mounted on the frame 13, with the possibility of translational movement along the guide rails 14, 15 of the frame 13, the bearings 16 and 17, the transmission gear 18, 19, the actuator 20 of rotation of the frame, movable bearings 21, 22 located in the buildings of pinola 23, 24. The quill mounted on bearings 25 - 27 buildings grandmothers - 28, 29. Last mounted on the frame 13 can move along the guide rails 14, 15. The end pieces 30, 31 pinola 23, 24 act as grips for the implementation of the twisting and stretching of the workpiece 32 (mechanism workpiece clamping grippers in Fig. 1 is not shown). In addition the device is equipped with actuators 33, 34 to move the movable supports 21, 22 and the loading of the workpiece 32 axial force actuators 35, 36 to move pinola 23, 24 with grips - 30, 31, and the electric motors 37, 38, which through gears 39, 40, the bearings 41, 42, 43, 44 and gear pairs 45, 46 and 47, 48 provide a torsion of the workpiece 32.

In Fig. 2 is a diagram of the processing of the workpiece. It is shown moving in the direction along the axis of the workpiece 32, and also performed with the reverse rotation of the bearings 21 and 22, the clamps 30 and 31, three angled 120oroller 3, 4 and 5.

In Fig. 3 shows the scheme which the train is made with the possibility of reversing the rotation of the supports 50 and 51, equipped with grippers 52 and 53, oven 54 to heat the portion of the processed part of the sample 55. On the end surfaces of the sample 49 made slots 56 and 57 for transmission of torque. The processed section 55 49 sample covered by the pads 56, 57, replacement rollers to maintain its stability in the sediment. The yoke 56 is used to hold the inserts in the sediment and torsion. The yoke and inserts made of a less durable material than the sample.

Example 1. The implementation of the method using the device shown in Fig. 1, illustrated by the scheme shown in Fig. 2.

Take the workpiece 32 in the form of a rod whose length is larger than the diameter several times. Before processing a rod mounted in bearings 21, 22 and the grippers 23, 24. To the selected processing station down the furnace 2 and the rollers 3, 4, 5, by shifting the carriage 12 to the frame 13 along the axis of the workpiece.

In the General case, the choice of a site for processing can be arbitrary, in specific cases depend on processing tasks. If you want to handle non-terminal site of the billet, the end of the last feature on the supports 21 and 22 and the grippers 23, 24, and rollers 3, 4, 5 together with the furnace 2 through the carriage 12 bring the workpiece to chase, thus the rollers perform the first role of support. (Fig 2B).

After reaching the temperature of deformation of the workpiece is put into rotation. The reduction produced by the relative run-in rollers 3, 4, 5 plot, when relative rotation of the workpiece 32 and the frame 1, and the simultaneous movement of the rollers in the transverse direction to the axis of the workpiece 32 under the action of hydraulic cylinders 9, 10, 11. To improve the process of reducing the end portion of the workpiece and prevent the formation of ridges on the surface neuregulirovannaya part of the workpiece axis of rotation of the rollers cross the axis of the workpiece at right angles at which there occurs a force directed along the axis of the workpiece. This force provides the offset displacement of the metal in the direction of the machined end of the workpiece. If not reduced the tail section, as shown in Fig. 2B, the workpiece applied axial tensile force F by means of the grippers 23, 24. In this case, as in the previous, reduced or practically not formed ridges of displaced metal rollers, because the combined effect of the rollers and grippers on the workpiece to provide the offset ends of the workpiece by an amount matching the plot limit length is heated to a temperature deformation part, and besides, if this area in the future will settle the amount, not exceeding three diameters of the reduced section. In Fig. 2G shows that the length of the reduced section is greater than the length of the rollers on the value . Next to the workpiece is applied in the opposite direction moments - M, providing plastic torsion of the treated area. In the process of plastic torsion also produce a running-surface section rollers. After torsion, depending on the requirements of the rod, move the rollers with oven or along the axis of the workpiece and start processing the next segment, or produce subsidence of the land.

Moving to a new area perform a variety of techniques: step - by transverse removal of the rollers from the workpiece, the displacement along the axis and re-introduction to a new site, or by moving the rollers along the axis of the workpiece, while the axis of proper rotation rotate about the axis of the workpiece for the above reason. It is also possible the simultaneous movement of the rollers along and across the workpiece with application to the workpiece tension.

Subsidence of the land is performed by application to the harvesting effort seaside can be performed by various techniques. One of them is demonstrated in Fig. 2 in Fig 2D. Front draft rollers occupied the extreme right position so that between them and the edge of the area was the gap . Then the position of the rollers and the right support was fixed, and the left support shifted by an amount sufficient to force P to besiege the left part of the treated area to the amount at which the gap vanishes. According to another reception draught produce the entire length of the treated area, with support actively (with movements) affect the workpiece forces P, while the rollers move in the transverse direction in concert with the growth of the diameter of settling parts so that they tried the surface of the workpiece and prevent Bochorishvili. In this case, the force of the overpressure limit so that it does not lead to growth of the upsetting enough to cause plastic deformation of the workpiece in the uncultivated parts or result in the loss of its stability. To reduce the efforts of precipitation and increase the homogeneity of the deformation simultaneously with the draft implementing plastic torsion of the processed section of the rod. Finally, the simultaneous combination of the above techniques at upsetting.

After completing clicks the positioning between the supports will not be processed. Fig. 2E, 2ZH.

The end of the procurement process, using the same techniques as for its beginning. Clearly sludge end pieces shown in Fig. 2H.

Example 2. Pilot testing of the methods was carried out on a number of alloys. The majority of experiments performed on two-phase titanium alloy DT8 with the original crude lamellar structure. This is because titanium (+) alloys are prone to localization of deformation, and plate morphology-phase is stable enough, for these reasons, they usually harder than Nickel alloys, to form a homogeneous microcrystalline structure. In addition DT8 were used in the experiments multiphase heat-resistant Nickel EP 962-phase alloy - nichrome HN.

To reduce the cost of experimental tests performed on a small model samples with a diameter of 15 and a length of 50 mm, using the device, the scheme of which is shown in Fig. 2.

Example 2.1. The aim was to identify the possibility and conditions for obtaining regulated structures, including homogeneous globular microcrystalline structure on one of the sections of samples in two-phase titanium alloy DT8. This task reseblance had lamellar microstructure (Fig. 4) with the size of the transformed grains 1500 to 2000 μm and colonies-phase - 200 - 300 µm. Plot for processing the samples had a diameter and length equal to 10 mm When compressed within this area received the sizes of cross-sections close to the original. Samples No. 1, 2, 3 were treated in accordance with the method at a temperature of 950oC, and the sample No. 4 at 750oC for the various modes shown in the table. There, the results from this experiment.

Example 2.2. The aim was to obtain a microcrystalline structure in the harvesting of heat-resistant Nickel alloy. A sample similar to the above, from coarse-grained heat-resistant alloy EP with an average grain size of the matrix 100 μm was mounted in the grips of the device described in Fig. 3, and heated to a temperature of 1080oC. First reduced section billet machined plastic torsion. The torsion produced up until the moment of torsion is not stabilized to a value of 5% from some mean value. Then made a draft of the plot up to a diameter approximately equal to the original, at the same time with torsion, with a total degree of deformation of about 3.8. Metallographic inspection showed that the alloy was formed LASS="ptx2">

Thus, the method provides a grinding grains in different materials. In addition, we checked the possibility of obtaining, in accordance with the method of structurally heterogeneous workpiece.

Example 2.3. Processed billet of titanium alloy DT8. The aim was to obtain a heterogeneous workpiece size 15 and a length of 20 mm, in which the material in the end portions, at a distance of about 5 mm from the ends would be fine, and enclosing between them the part with coarse lamellar structure. In accordance with this task handled by the regime, similar to that shown in example 2.1 under N 4, two sections for a length of 10 mm and at a distance of 20 mm from each other in the coarse-grained sample with lamellar structure. Then cut the sample by means of the treated areas. The resulting billet was besieged by 75% on the press with a speed of 10-3with-1at a temperature of 950oC. For comparison, the same conditions also besieged homogeneous coarse-grained billet. The precipitation results showed that in structurally heterogeneous workpiece was no developed barrel, no stagnant zones, and has developed an almost homogeneous globular structure. Meanwhile, after precipitation krupneishei degree passed transformation of the original structure in globular. This example demonstrates the feasibility of processing in accordance with the proposed method of individual sections of the workpiece.

Example 3. Due to the large expenditures required for the experimental verification of the method on a full-scale long workpieces of large diameter, in this example, theoretical evaluation of the effect of different techniques and modes of implementation of the method on the degree of deformation of the workpiece and energy-power parameters and identifying the most optimal of them. In addition, it was estimated by such important for the practical implementation of the method factors as the processing time of the workpiece in this way, the value of the effort, providing draught plot without buckling of the workpiece. The calculations were performed according to the mathematical model described in the Appendix to the application materials. Below are presented the main results of the calculations.

The results show that the optimum conditions, the method in many cases, for example for grinding grains, is the simultaneous combination schemes deformation, in particular the reduction of (tensile) and a draught advantageously be performed simultaneously with torsion. This approach gives swale necessary for grinding grain deformation, and in the reduction of the axial forces. In particular, the torsional force precipitation plots of workpieces with a diameter of from 100 to 250 mm are less than 10 tons at a speed of deformation of 5 mm/min and up to 60 tons at a speed of deformation of 50 mm/min. If you make a draught without torsion, then the necessary efforts in 3 - 5 large. For comparison, it should be noted that in order to get by extrusion (extrusion) rods with a diameter of 100 - 250 mm with microcrystalline structure of heat-resistant Nickel and titanium alloys required press force of several thousand tons. Calculations show that required for precipitation in combination with torsion efforts provide the billet deformation without losing its stability, i.e. these efforts below the critical, causing bending of the workpiece. The torque required to twist the workpiece 100 to 300 mm, respectively 1 - 14 TM.

Processing time per parcel, necessary for obtaining a fine-grained structure, is a few minutes, and the time required to obtain such a structure in the rod with a diameter of 200 mm and a length of about 2 m, will be about 2 hours. For comparison, this time comparable with the time of the comprehensive forging billets with a diameter of 200 mm and a length of 400 - 500 erties in advanced metallic materials / Proceed. of the First Int. Conf. on Processing Materials for Properies. Held in Hordaie, November 7-10, 1993. A Publication of TMS - Minerals - Metals - Materials, pp. 971-974.

2. KUZNETSOV R. I., BYKOV V. I., V. CHERNYSHEV, P. et al. Plastic Deformation of Solids Under Pressure. I. Apparatus and Techniques. Sverdlovsk, Russia, Ural Branch of the Academy of Sciences of USSR, 1985 (in Russian).

3. A. S. N 940987, B 21 J 5/00. "A method of materials processing pressure", 23.09.80, C. E. Kobzov, A. K. Popov, Doctor of historical Sciences, the Shakhnovsky.

1. The method of machining of metals and alloys, including deformation of at least part of the workpiece through various schemes, including leading to reduction of its cross-section, characterized in that the charge of the workpiece in the form mainly of lengthy rod, the reduction performed by the tool, with the possibility of relative displacements along and across the axis of the workpiece and relative to the running surface, for example, roller, using at least two supports, which include procurement, and the desired degree of deformation provide, using at least also one of the schemes deformation sold torsional, upsetting or stretching through a tool, for example, the supports are made with the possibility of impacts on the workpiece corresponding to the diagrams of deformation forces when TST in the workpiece material.

2. The method according to p. 1, characterized in that in the case of a relative break the surface of the rod by more than one roller use one leg.

3. The method according to p. 1, characterized in that the reduction of area is performed with the application to the workpiece tensile axial forces through the poles with hooks.

4. The method according to p. 1, characterized in that the reduction of area is performed by cross-rolling the billet rollers.

5. The method according to p. 1, characterized in that the reduction is accomplished by the longitudinal-transverse rolling of billet rollers.

6. The method according to p. 1, characterized in that the reduction is performed by rolling the billet rollers, the axis of rotation of which form the skew angles with the axis of the workpiece.

7. The method according to p. 1, characterized in that the reduction of the workpiece produced by the three rollers are arranged relative to each other with an interval of 120o.

8. The method according to p. 1, characterized in that the length of each treated area does not exceed three minimum rod diameters in the reduced section.

9. The method according to p. 1, characterized in that the pressure reduction section performs under the action of compressive along the your bearings and rollers.

11. The method according to p. 1, wherein producing a reversible torsion.

12. The method according to p. 1, characterized in that the deformation plot produced using curly roller, the profile of which is formed with average maximum dimensions of a part, which is converted from its ends, the intermediate part and the next, beginning with the smallest cross-sectional dimension of the intermediate section, two end sections.

13. The method according to p. 1, characterized in that draft procurement section is executed after lateral movement of the rollers in the direction from the axis of the workpiece by an amount not to exceed the absolute value of the transverse deformation of this area when it is reducing.

14. The method according to p. 1, characterized in that draft procurement section is performed after the longitudinal-transverse movement of the rollers relative to the axis of the workpiece.

15. The method according to p. 1, characterized in that draft procurement section performed simultaneously with the rolling surface of the rollers with respect to the conditions:

u>i< e,

whereithe stress intensity rainfall area defined with the resistance to deformation provided by the rollers during running;

u- Zaydee compression undistorted areas of the workpiece.

16. The method according to p. 1, characterized in that the deformation continuously perform consistently along the entire length of the workpiece.

17. The method according to p. 1, characterized in that the portions of the workpieces from a single-phase alloys deform with the true degree of deformation of at least 3, including in combination with the degree of not less than 1.4, and the deformation is carried out at speeds of 101- 10-2with-1at the temperature of (0.3 to 0.5) TPLwhere TPLthe melting point of the workpiece material.

18. The method according to p. 1, characterized in that the side pieces of multiphase alloys deform with the true degree of deformation of at least 2, including in combination with the degree of not less than 1.4, and the deformation is carried out at speeds of 10-1- 10-4with-1when the temperature (from 0.5 to 0.85)TPLwhere TPLthe melting point of the workpiece material.

19. The method according to p. 1, characterized in that the part of the billet of titanium alloy with lamellar structure is deformed with the true degree at least 3 reduction, torsion simultaneously running rollers and rebuff with simultaneous running rollers, and torsion combined with the reduction and subsidence, and deformation is carried out at and polymorphic transformation of the workpiece material.

20. The method according to p. 1, characterized in that the part of the billet of titanium alloy with lamellar structure is deformed with the true degree at least 3 reduction, torsion simultaneously running rollers and rebuff with simultaneous running rollers, and the deformation is carried out at a temperature of 700 - Tp. pand strain rates of 10-1- 10-4with-1where Tp. pthe temperature of polymorphic transformation of the workpiece material.

21. The method according to p. 1, characterized in that the reduction plots billet of titanium alloy with lamellar structure is carried out to reduce the cross-sectional area not less than 1.1 times at temperature Tp. pto Tp. p+ (10 to 50), then the plot is cooled at a rate not less than 1o/s, and the torsion and the precipitate is carried out with the running rollers simultaneously at a temperature not exceeding 700 - Tp. pwith strain rates of 10-1- 10-4with-1where Tp. pthe temperature of polymorphic transformation of the workpiece material.

22. The method according to p. 17, characterized in that the parts of the blank of heat-resistant Nickel alloys deformed at a temperature not higher than the temperature of complete dissolution of the intermetallic phase.

fmore than 5 - 10%.

24. The method according to p. 1, characterized in that the deformation at each site produced under prescribed conditions of temperature and strain rate up until the abrupt change in the strain rate will not lead to an increase of the speed ratio of the sensitivity - m = (logN1-logN2)/(log1-log2) to values in the range 0.3 to 0.8, where N1N2- load (torque, tension, compression or tension when the corresponding type strain), acting on the workpiece before and after the speed change from the value of1to the value of 2.

 

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SUBSTANCE: wire production line includes multi-row disc shears for slitting coiled material; unit for working wire ribs; apparatus for plastic working of wire in the form of rotor with axial opening for wire. Said apparatus is mounted with possibility of rotation around wire from drive unit of rotor. Line also includes at least one pair of rolls mounted in rotor with gap for passing wire. Said rolls are mounted with possibility of rotation from drive unit of rolls in direction of wire feed. One roll is cylindrical, other roll has working protrusion with cylindrical surface or several such protrusions mutually spaced by intervals.

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1 tbl, 2 dwg

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1 dwg, 2 tbl, 1 ex

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