RU2187403C2 - Method for making complex-profile axially symmetrical parts of hard-to-form multiphase alloys and apparatus for performing the same - Google Patents

Abstract

FIELD: plastic metal working, possibly manufacture of precise blanks of such parts as complex-shape discs with significantly changed thickness and diameter and with deep non-formed undercuts from hard-to-form multiphase alloys, particularly from refractory nickel alloys. SUBSTANCE: method comprises steps of placing shaped blank with possibility of its fixation and rotation; subjecting its peripheral portion to local shaping at temperature values no higher than 0.4 of its melting temperature but lower than temperature of planned recrystallization at rate 10^-3-10²s^-1 1/s; performing local shaping at squeezing peripheral part of blank at least by means of one roller in direction of its generatrix onto mandrel simultaneously used for fixing central portion; setting time period of blank rotation relative to local tool no less than time period of intensive relaxation of stresses in deformed zones. Apparatus for making parts includes units for axial fixation and rotation of blank provided with attachments for mounting mandrels; at least one roller with roller holder and working furnace. The last has in its walls openings for introducing part of unit for fixing rollers. Actuating mechanisms are designed for rotating and moving rollers. Walls of furnace have movable portion arranged around opening for introducing roller with possibility of axial motion together with roller along the whole length of its working stroke. EFFECT: enhanced efficiency, enlarged manufacturing possibilities of method, simplified design of apparatus. 25 cl, 23 dwg

Description

 The invention relates to the field of metal forming, in particular to methods for producing precise workpieces of parts such as disks of complex shape with significant differences in thickness and diameter, with deep non-stampable undercuts made from hard to deform multiphase alloys, in particular from heat-resistant nickel alloys.

A known method of manufacturing parts from difficult to ^deform alloys by stamping a fine-grained workpiece in superplastic conditions, known as "Gatorizing ^TM" [1]. At the first stage, the method of intensive plastic deformation (extrusion with large hoods) produces a superplastic semi-finished product, which is stamped in the second stage. This method allows to obtain axisymmetric parts of relatively complex shape, for example, disks of small diameters with blades. However, its capabilities are very limited by the disadvantage of the stamping method, which consists in the fact that almost every product is made in the corresponding stamp. Therefore, with an increase in the product range, the number of expensive dies is growing. In addition, for the implementation of the method requires a powerful press equipment and massive expensive die tooling.

The closest in technical essence is a method of manufacturing complex axisymmetric parts from difficult to deform multiphase alloys having a central and peripheral, mainly in the form of a rim, part, including installing a profiled workpiece with the ability to fix and rotate it and local shaping of the peripheral part at temperatures above 0.4 temperature melting, but lower than the temperature of collective recrystallization, at a rate of 10 ^-3 -10 ² s ^-1 using a tool for local deformation in the form of a roller having at least three degrees of freedom [2].

 This method allows to produce axisymmetric parts of complex design.

In a generalized form, the favorable distribution of the stress state in the workpiece reflects the following relationship:
σ _s > q≥σ _τ (1)
where σ _τ is the stress of the flow of the workpiece material in the deformable zone of the peripheral part;
σ _s - is the deformation resistance of the workpiece material in the deformed zones of the peripheral and central parts;
q is the pressure (specific force) of the tool on the workpiece.

 However, there is a large class of axisymmetric parts with central and peripheral parts, in which the peripheral part differs not only in a complex profile and developed surface, but significantly exceeds the central part in volume and surface area. In addition, often the shape of the peripheral part is non-stampable because it has a tapering or undercut cavity. The prototype does not allow us to solve the problem of obtaining such parts because in order to form a peripheral part that is complex in shape and has an extensive surface area, it is necessary to roll a massive peripheral part of the workpiece with large degrees of deformation. This can only be done under conditions of hot deformation, including superplastic, providing high plastic properties of the material. Despite the fact that under these conditions, the flow stress of the metal is small, deformation (displacement) of the massive volume of the peripheral part requires large loads — forces and specific forces, which are greater, the greater the so-called “hard end” of the deformable workpiece. In essence, the hard end in the rolling under consideration is a zone of (constrained) difficult deformation, characterized by the distance between its outer and inner diameters. During rolling, the rollers exert pressure on the inner surface of the rim, but in order for the workpiece to increase in diameter, the deformation zone must be developed to the outer surface of the rim. The greater this distance, the greater pressure (specific force) the tool must act on the workpiece. The value of the hard end can be estimated by the ratio of the above diameters. If this ratio is greater than the value of 1.5 -1.8, then it is necessary to apply such pressures and forces that will lead to a change in size and shape also in the thin disk part already formed by rolling — in the sheet. The ratio of the axial dimensions of the central and peripheral parts, i.e. rolled rim and rolled web. Therefore, the volume and mass of the rolled peripheral part of the disk as a whole is also limited.

 Used in the prototype methods of preventing deformation of the canvas do not provide a solution to the problem of rolling the workpiece with a more massive than acceptable peripheral part. So, in the prototype increase the resistance of the fabric by hardening the material as a result of its undermining. However, the degree of possible reinforcement is limited by the thermal conductivity of the material and the danger of overcooling of the deformable part to critical temperatures at which the alloy ductility decreases, flow stresses increase and this again leads to an increase in deformation forces. In other cases, unregulated cooling leads to heterogeneity. It is also impossible to significantly reduce the radial deformation rate, since this will reduce the contact spot of the tool with the workpiece, the deformation zone, which will increase the effect of the hard end to a greater extent.

 One of the conditions for the implementation of local shaping by the prototype method is the presence of a workpiece with a structure prepared for superplastic deformation. The preparation of a fine-grained structure is carried out according to a separate rather labor-intensive technological process associated with the need for intensive deformation of the workpiece.

 Thus, in the manufacture of complex, large-sized axisymmetric parts from difficult to deform multiphase alloys, there is a problem of obtaining accurate parts with a complex shape and developed peripheral part.

 The objective of the invention is to provide a method for manufacturing of multiphase alloys of complex axisymmetric parts with central and developed peripheral parts while ensuring high productivity of forming.

 In addition, the objective of the method is the expansion of technological capabilities through the use of both workpieces with a fine-grained and coarse-grained structure and the corresponding structure of the deformation mode.

The problem is solved in that in the known method of manufacturing complex axisymmetric parts from difficult to deform multiphase alloys having a central and peripheral, mainly in the form of a rim, part, including the installation of a profiled workpiece with the possibility of its fixation and rotation and local shaping of the peripheral part at temperatures above 0, 4 melting points, but lower than the temperature of collective recrystallization, at a rate of 10 ^-3 -10 ² s ^-1 using a tool for local deformation in the form of a roller having at least three degrees of freedom, local shaping is carried out by compressing the peripheral part of the profiled workpiece in the direction of its forming by means of at least one roller on a mandrel that serves simultaneously to fix the central part of the profiled workpiece, while the rotation period of the workpiece relative to the local tool set no less than the time of intense relaxation of stress in deformable areas.

 Local shaping is carried out using a mandrel, the diameter of which corresponds to the inner diameter of the peripheral part of the profiled workpiece, using a workpiece, at least part of the profiled peripheral part of which has an external diameter exceeding the diameter of the finished part.

Local shaping is carried out using a mandrel, the diameter of which corresponds to the outer diameter of the profiled workpiece, using a workpiece, at least part of the profiled peripheral part of which has an inner diameter smaller than the diameter of the finished part:
the rotation period of the billets of aluminum alloys is selected no more than 0.25 s;
the rotation period of the workpieces made of titanium and heat-resistant nickel alloys is chosen in the range of 0.25-100 s;
the rotation period for preforms with a coarse-grained structure is selected within 50-100 s;
the rotation period for preforms with a fine-grained structure is selected within 10-50 s;
the rotation period for preforms with a submicrocrystalline structure is chosen within 0.25-10 s;
local shaping is carried out in one or more operations, the amount of which is selected depending on the preliminary profiling of the initial workpiece and its structure;
as the initial take a workpiece with a structure prepared for superplastic deformation, profiled in the form of a glass, local shaping is performed in one operation;
as the initial take a workpiece with a structure prepared for superplastic deformation, profiled in the form of a Central part and a peripheral protrusion, local shaping is performed in two operations, and in the first operation receive the workpiece in the form of a glass;
as the initial take a preform with a coarse-grained structure, profiled in the form of a central part and a peripheral thick-walled protrusion, local shaping is performed in two operations, and in the first operation, a preform is prepared in the form of a glass with compression of the peripheral part by 50-75% under temperature and speed conditions of superplasticity ;
the first shaping operation is carried out in several transitions using the reverse movement of the roller;
use a collapsible mandrel;
the temperature on the deforming surfaces of the mandrel is maintained in the temperature range of the superplasticity of the workpiece material;
upon receipt of a glass type part with a monotonously tapering profile, an additional operation of local shaping of the peripheral part of the preform is carried out using one roller;
upon receipt of a glass type part with a monotonously tapering profile, the local peripheral part is formed using one roller and a mandrel with an outer diameter equal to the minimum inner diameter of the peripheral part of the part;
carry out an additional operation of local shaping of the peripheral part of the workpiece using two rollers located on different sides of the formed wall;
carry out an additional operation of local shaping of the peripheral part of the workpiece using two rollers located on different sides of the formed wall and the mandrel, moreover, in the first operation using a roller and mandrel, and in the subsequent operation, rollers;
when forming parts from heat-resistant nickel alloys locally, they provide a heating temperature on the deformable surface of the peripheral part of the workpiece in the range from the deformation temperature to a temperature that exceeds the lower temperature threshold of superplasticity for fine-grained material.

 A device for the manufacture of complex axisymmetric parts having a central and peripheral, mainly in the form of a rim, parts of difficult to deform multiphase alloys, containing axial fixation and rotation of the workpiece, which are equipped with devices for installing mandrels, and at least one roller with a roller holder, a working furnace with holes in the walls to enter part of the fixing unit of the rollers and actuators to ensure rotation and movement of the rollers [2].

 This device uses a large number of drive rollers, any movements, including rotation, which require coordination both with each other and with the rotation of the part. The latter significantly complicates the design, increases the number of actuators, complicates the control and monitoring system. It is impossible to satisfactorily coordinate the speeds of rotation of the rollers in the case of rolling blanks having undercuts, the so-called non-stamped profiles.

 In addition, in order to deform the central part - the shaft, the introduction of cantilever rollers into the furnace to a great depth is required. This is only possible for parts with a very simple shaft type configuration.

 The device cannot be used for parts having a developed peripheral part in the form of a complex profile thin-walled rim having undercuts and significant differences in diameter in the axial direction.

 The objective of the invention is to provide the possibility of manufacturing parts such as a disk, a shell having a developed peripheral part in the form of a complex thin-walled rim having undercuts and significant differences in diameter in the axial direction while simplifying the device.

 To solve the problem in a known device for the manufacture of complex axisymmetric parts having a central and peripheral, mainly in the form of a rim, parts of difficult to deform multiphase alloys containing axial fixation and rotation of the workpiece, which are equipped with devices for installing mandrels, and at least one roller with a roller holder, a working furnace with holes in the walls to enter part of the roller fixing unit and actuators to ensure rotation and movement of the roller in, the furnace wall formed with a movable portion disposed around the opening for the entry roller to be movable in the axial direction together with the roller over the entire length predetermined stroke video.

 The fixing unit is equipped with devices for installing collapsible mandrels.

 The fixing unit is equipped with a shaft and bushings for transmitting torque to the workpiece.

 The roller holder is additionally equipped with a heat shield. The working furnace is additionally equipped with a separate chamber for placing the tool in it and preheating it.

 The chamber is combined with the movable part of the furnace wall.

 The result is the creation of a favorable distribution of stress-strain states (SSS) in the workpiece, in which the stress in the deformable zone is sufficient for plastic flow of the material in the direction specified by the tool, and in the rest it is less than the level that causes plastic deformation. At the same time, favorable VAT means not only the compliance of the strain values with the acquired form, but also the formation or preservation of the necessary deformation structure, in particular, without accumulation of defects dangerous for shaping or operation and, if possible, ensuring its uniformity.

 Let us evaluate the influence of geometric factors - the dimensions of the displaced volume of the workpiece and the strain rate - on relation (1), which reflects in a generalized way the favorable distribution of VAT.

The average pressure q exerted by the roller on the workpiece is determined as
q = F / S, (2)
where S is the contact area of the tool with the workpiece, F is the total force of the tool on the workpiece in the contact spot.

The magnitude of this effort can also be represented through internal stresses in the deformable body.
F = n _σ σ _i S, (3)
where n _σ is the stress coefficient. It depends on the value of the hard end, σ _i is the intensity of internal stresses.

With sufficient accuracy for engineering analysis, it can be accepted that deformation with a given speed in the deformable peripheral part occurs when the stress intensity σ _i reaches a certain value of σ _τ - flow stress. Moreover, σ _τ - depends on the strain rate ξ
σ _τ = Kξ ^m , (4)
where K is the empirical coefficient, m is the velocity sensitivity of the flow stress.

Using expressions (2), (3) and (4), we obtain
q = n _σ Kξ ^m . (5)
In the latest equations, ξ is the average for one revolution (over the period of rotation of the workpiece relative to the roller) the strain rate of each local section. The instantaneous strain rate ξ _m of the section can be defined as
ξ _m = V / L, (6)
where V is the speed of run-up metal of the workpiece on the tool, L is the contact length of the workpiece with the tool in the run-in direction.

With a constant value of tool crimping (towards the axis in the proposed method and between the rollers in the prototype), the speed V consists of two components: V _τ is the peripheral speed of rotation of the workpiece and V _a is the axial velocity of the tool (for the prototype, this is the radial speed - V _r ) In a scalar form, the linear velocity equation can be written as V = (V $\genfrac{}{}{0ex}{}{\text{2}}{\text{τ}}$ + V $\genfrac{}{}{0ex}{}{\text{2}}{\text{a}}$ ) ^1/2 . Given the latter we get:
ξ _m = V / L = (V $\genfrac{}{}{0ex}{}{\text{2}}{\text{τ}}$ + V $\genfrac{}{}{0ex}{}{\text{2}}{\text{a}}$ ) ^1/2 / L (7)
The average speed per revolution will be:
ξ = ξ _m Δt / T, (8)
where Δt is the time spent by the local area (contact spots) under the tool, T is the period of rotation of the workpiece.

ξ≈τ^-1•[1+(V_a/V_τ)²]^1/2. (10)
После подстановки выражения (10) в выражение (5) получим:
q≅K•n_σ•τ^-m•[1+(V_a/V_τ)²]^m/2, (11)
или, если учесть, что V_τ = ωR; а ω = 2π/T в другом виде:
q≅K•n_σ•τ^-m•[1+(V_aτ/2πR)²]^m/2 (12)
Выражение (12) справедливо для предлагаемого способа и для прототипа, только в последнем случае вместо V_a надо подставит скорость V_r.In turn, T = Δt + τ, where τ is the idle travel time of the deformable section, and τ >> Δt, therefore, we can assume that T≅τ, then ξ≈ξ _m Δt / τ.
The parameters used are interconnected as follows: -Δt = L / V _r ; V _r = ωR; ω = 2π / T, where ω is the angular velocity, R is the current radius of deformation of the peripheral part, π≈3.14.
Hence, the instantaneous and average speeds can be respectively represented as:

ξ≈τ ^-1 • [1+ (V _a / V _τ ) ² ] ^1/2 . (10)
After substituting expression (10) into expression (5), we obtain:
q≅K • n _σ • τ ^-m • [1+ (V _a / V _τ ) ² ] ^{m / 2} , (11)
or, taking into account that V _τ = ωR; and ω = 2π / T in another form:
q≅K • n _σ • τ ^-m • [1+ (V _a τ / 2πR) ² ] ^{m / 2} (12)
Expression (12) is true for the proposed method and for the prototype, only in the latter case, instead of V _a, it is necessary to substitute the speed V _r .

In expression (12), the value of the expression, enclosed in square brackets, is close to unity, because when forming large parts, the circumference (2πR) significantly exceeds the tool feed per revolution (V _a τ) and, therefore, the ratio (V _a τ / 2πR ) ² is a small quantity.

After simplification (12) we get:
q≅K • n _σ • τ ^-m (13)
Thus, the equation (13) common to the method and prototype under consideration shows that if we do not take into account the coefficients K and m, which reflect the influence of the structure, and this is quite acceptable for hot deformation under SPD conditions, then the pressure depends on the period -τ. Since τ is located in the denominator, with its growth q - decreases, and with decreasing q it grows. However, the change in the period does not equally affect q for the proposed method and prototype due to the coefficient n _σ . So the reduction of the period in the proposed method leads to an inversely proportional increase in q, because the hard end here does not affect q and the coefficient n _σ is an almost constant number close to unity in value.

In the prototype, the pressure depends on the dimensions of the rigid end and the deformation zone. The coefficient n _σ nonlinearly depends on these parameters. With increasing strain rate, the value of stresses acting in the deformable region increases. As a result, the intensity of these stresses σ _i changes, and in order for it to again reach the increased value of the flow stress σ _τ corresponding to the increased speed, it is necessary to additionally increase the tool pressure.

Therefore, as a result, with an increase in the strain rate, the pressure increases uneasyly due to an increase in the flow stress due to this speed, and also due to the influence of the hard end. This influence reflects the coefficient n _σ , which varies from 2 to 5. Therefore, the same specific tool force on the workpiece corresponding to condition (1) in the proposed method provides a higher level of flow stress σ _τ in the peripheral part and, accordingly, greater deformation rate and performance compared to the prototype.

 Thus, the absence of the mutual influence of the period and the stress state coefficient can significantly increase the effect of increasing the voltage from reducing the rotation period in the proposed method, subject to condition (1).

Moreover, in the proposed method, productivity can be increased not only by reducing the rotation period of the workpiece, but by changing the ratio between the speeds V _a / V _τ . In the prototype, this can not be done, as noted earlier, because with decreasing V _r . the influence of the stress state scheme is enhanced, and with an increase in V _τ , the moment leading to deformation of the formed part increases, as will be shown below.

 The choice of the rotation period is associated with the features of deformation during local shaping of the peripheral part.

 The nature of the deformation in the proposed solution is such that each section of the deformable peripheral part is repeatedly subjected to cyclic action of the tool due to the fact that the workpiece rotates relative to the tool and the tool moves sequentially in the direction of the forming peripheral part. During the direct action of the tool within the local deformation zone, shear stresses act in it, displacing the workpiece material in the direction specified by the tool. After any area comes out of contact with the tool and during its idle run until the tool is exposed again, the material relaxes and the stresses induced by the tool are reduced. At the microstructural level, the density of defects decreases during relaxation, for example, due to annihilation of dislocations. Since the deformation zone at the tool impact area exceeds, especially for a fine-grained structure, the zone of direct contact of the workpiece with the tool, i.e. the length of the focus in the direction of the generatrix is noticeably greater than the feed rate of the tool per revolution, then part of the material when the workpiece rotates relative to the tool is repeatedly exposed to the tool again and again. When the workpiece rotates with a period not exceeding the time of intensive relaxation, the stresses decrease several times, and defects that significantly change its structural state and mechanical properties, in particular, shear stress and ductility, do not have time to accumulate in the material. Proof of this are specially performed experiments. They determined the time of intense relaxation of flow stresses after unloading under tension of the sample. At the same time, the levels of plasticity and flow stresses of the samples subjected to continuous stretching and intermittent (cyclic) stretching were compared. In this case, intermittent tension was performed with unloading the sample with a rest time longer than the time of intense stress relaxation. It was found that in a high-temperature-resistant alloy, stresses drop several times over a time of the order of 1-5 s. In addition, the stress level of a sample cyclically deformed with a given period was approximately the same as that of a subjected to continuous deformation, and the relative elongation was 1.5-2 times greater.

In the prototype, with a decrease in the rotation period of the workpiece relative to the part, the tangential component F _{τ of the} force will increase, forming the moment. This moment together with the radial component F _r act in the same rolling plane, respectively twisting and stretching the sheet in its minimum section. It is impossible to significantly reduce the component F _r , since the deformation zone must be developed. Therefore, with a decrease in the period, the sum of the forces acting on the deformed part will increase.

In the proposed method, an increase in F _τ due to high-speed hardening does not significantly affect the growth of stresses in the formed part, because this force is less than in the prototype, since the contact area is smaller in the corresponding direction. The other component, the axial force F _{a, is} also not so large and can be set within the required value in two steps, the first one due to the choice of q in accordance with the above relations, and the second one due to the variation of S, since the method can be implemented in one transition (large S), and for several transitions (small S), since there is no influence of the hard end. Therefore, in the proposed method, it is easier to fulfill condition (1).

 Thus, the sign that the workpiece is rotated with a period not exceeding the time of intensive relaxation of the deformed sections is one of the main and sufficient to create a favorable deformed state of the material that allows it to deform with large degrees of deformation without accumulating defects, and one from necessary to solve the problem.

 To increase productivity and comply with relation (1) - i.e. favorable VAT, it is advantageous to reduce the period of rotation of the workpiece to the relaxation time and to reduce the axial velocity of the tool over the period, i.e., the feed of the tool for each revolution of the workpiece. The linear tool speed will be determined by the product of the number of revolutions per feed per revolution. In addition, with a decrease in the axial velocity, the corresponding force, which acts as tensile with respect to the formed zone of the peripheral part, will also decrease, i.e., the conditions for fulfilling relation (1) will improve.

 The use of pins in the method as a mandrel improves the VAT at least when deforming the peripheral part of preforms with a coarse-grained structure, in which the flow stress is greater than that of a fine-grained structure. This is facilitated by friction forces directed in the opposite direction to the forces considered above, which tend to change the shape and dimensions of the deformed peripheral part.

 Finally, we note that the formation of the peripheral part in the direction of its generatrix is not the only and unequivocally possible for the local shaping of parts with a developed peripheral part. Such parts can be made according to another scheme and from a preform profiled differently than in the proposed method. In particular, from a workpiece, the peripheral part of which is profiled in the plane of the central part, which can then be "laid" on a mandrel by rotary compression. However, this way does not provide a solution to the problem. Moreover, in the process of preliminary formation of the peripheral part, for example by the same rolling, to the required size, all the disadvantages inherent in the prototype prevent this.

 In additional points, the relaxation time depends on a number of factors, temperature, nature of the alloy, and structure. The higher the superplastic deformation temperature (SPD) and the smaller the grain size, the faster the stress relaxation processes. At the same time, for example, for heat-resistant alloys during deformation at a temperature corresponding to the lower SPD interval, a longer period is required, and for fine-grained ordinary alloys that are deformed at a high SPD temperature, a short period is 5. For titanium alloys 5, and for aluminum alloys 0, 25.

 Relatively small periods of repeated actions during the formation of the peripheral part are especially favorable for local deformation of workpieces with a fine-grained structure, since relaxation processes proceed rapidly in it and this structure provides high technological plasticity of the workpiece material. The influence of the nature of the alloy on the rotation period and relaxation time is ambiguous; in multiphase heat-resistant alloys based on nickel or titanium, the relaxation time is longer than, for example, in aluminum alloys. However, the first materials have low thermal conductivity compared to the second. That is, a local temperature increase due to deformation can accelerate relaxation, at the same time, the heat released should not lead to unacceptable overheating. Experimental verification showed that the rotation period during the shaping of titanium and heat-resistant billets should not be higher than 100 s.

 Other additional significant features also develop and clarify the possibilities of solving the problem.

 According to the method, the peripheral part is shaped by a mandrel.

 The presence of friction on the developed contact surface between the workpiece and the mandrel in the proposed method, in contrast to the prototype, allows for lower contact stresses (pressing pressure) to ensure the rotation of the workpiece with local shaping. Moreover, in the proposed method, only one of the three vectors of strain forces exerts an impact in the form of a moment on the central part. However, the stresses in the central part from this moment are small, since they, in contrast to the prototype, are reduced by a large value of the polar moment of resistance of the central section.

 In the manufacture of parts whose peripheral zone forms the shape of a tapering glass relative to the web, the deformation of the peripheral zone is performed in two stages, first obtaining a shape in the form of a tapering glass with a diameter not less than the diameter of the bottom, and then crimping it on a collapsible mandrel or without a mandrel by stretching the walls to final sizes.

 Local shaping is carried out in several operations, the amount of which is determined depending on the degree of preliminary profiling of the workpiece and structure. This is due to the fact that the initial billet can be obtained by various metallurgical methods, for example, casting, stamping, powder metallurgy, or a combination thereof.

 In particular, if it is possible to use a billet profiled in the form of a glass with a structure prepared for superplastic deformation, the number of local shaping operations can be reduced to almost one operation.

 At the same time, the method is feasible if you use a workpiece with a structure prepared for superplastic deformation, profiled in the form of a central part and a peripheral protrusion.

 Moreover, it is advisable to use a preform profiled in the above manner if it has an initial coarse-grained structure. Here, a prerequisite is the presence of a thick-walled protrusion, which, upon subsequent deformation, provides the transformation of the microstructure into micro- or submicrocrystalline.

 Regardless of the final profile of the part, it is recommended that in the first operation of local shaping, a bead-shaped workpiece is obtained using a mandrel. In some cases, this may be the final form of the part.

 If it is necessary to obtain a part with an extended, thin-walled peripheral part, it is recommended that the shaping be carried out in stages in several transitions. This creates optimal conditions for the application of the deforming load. By varying the path of the tool - the roller, changing its inclination relative to the axis of rotation of the workpiece, as well as the depth of introduction of the roller, it is possible to widely control the degree of deformation at each transition and thereby provide the most favorable conditions for the deformation of the peripheral part. This circumstance is very important for the case of using a workpiece, in which a coarse-grained structure is formed in the peripheral part in the initial state. As is known [3], the coarse-grained structure is characterized by a very limited resource of technological plasticity during hot deformation, which can lead to disruption of the material continuity when trying to produce axisymmetric parts with developed thin-walled peripheral parts from hardly deformed materials. Therefore, when using a preform in which the peripheral part has a coarse-grained structure, it is necessary at the first transitions to ensure its transformation into microcrystalline with a grain size of 1-10 μm or submicrocrystalline with a grain size of less than 1 μm, i.e. prepare a structure capable of superplastic deformation.

 The choice of specific values of the degrees of deformation and temperature and speed conditions, at least for the part of the transitions necessary to ensure the preparation of the structure for superplastic deformation, is determined by many factors: the chemical and phase composition of the alloys, the final profile of the peripheral part of the part, the requirements for the structure and mechanical properties of the final the details. The degree and temperature-speed conditions of deformation are chosen sufficient to undergo dynamic recrystallization in the material, during which a microcrystalline structure is formed. It should be noted that the microcrystalline structure can be formed in the peripheral part in several transitions. At the first transition, a partially recrystallized structure is formed and then at the second, which may be final, a completely recrystallized structure is formed in the peripheral part. This technique will significantly reduce the magnitude of the specific efforts, as well as contribute to a more complete relaxation of stresses. This is especially important for multiphase alloys. In particular, for example, in dispersion hardening nickel alloys at the first stage, it is necessary to eliminate the strengthening effect of the second phase due to its coagulation, violation of the coherent bond with the matrix and its partial dissolution. A small degree of deformation at the first transition significantly accelerates the coagulation processes of the second phase, and the choice of the maximum values of the workpiece rotation period creates more favorable conditions for stress relaxation due to the occurrence of dynamic polygonization and recrystallization processes leading to the formation of a partially recrystallized structure.

 In addition, the use of several transitions allows to reduce the temperature from the transition to the transition and this contributes to the additional refinement of the microstructure in the peripheral part to submicron sizes. The presence of a submicrocrystalline structure in the peripheral part of the preform makes it possible to significantly reduce the stress relaxation period, thereby increasing the productivity of the process.

 The technological capabilities of the method are enhanced by the technique in which shaping is carried out using the reverse movement of the roller. In this case, repeated deformation is carried out by analogy with reverse extrusion. Due to this, the productivity of the process increases.

 One of the recommended conditions for obtaining parts with significant differences in thickness and diameter in adjacent sections is the implementation of local shaping of the peripheral part using a mandrel. This facilitates compliance with condition (1), which ultimately increases the accuracy of manufacturing parts in geometry and dimensions.

 Structurally, the mandrel can be made integral or collapsible. The choice of one or another design of the mandrel is determined by the profile of the peripheral part of the part. In those cases when the peripheral part of the part has a profile with a decreasing outer diameter and ends with the formation of a flange, i.e. when after forming it is not possible to remove the mandrel from the internal cavity of the part, a collapsible version of the mandrel is used.

 The mandrel can be both external and internal, depending on the profile of the inner and outer surfaces.

 The mandrel is usually made of a more heat-resistant material, for example, of cast high-alloy nickel alloy. To ensure structural strength, the mandrel is also made more massive than the workpiece. Since the mandrel is constantly in direct contact with the deformable workpiece, intense heat transfer takes place, especially if local mandreling of the mandrel through the fixation unit of the central workpiece with the mandrel is used. In this case, it is recommended to strictly control the heating temperature of the mandrel so that the temperature on the deforming surfaces of the mandrel corresponds to the temperature range of the superplasticity of the workpiece material.

 In the manufacture of thin-walled parts such as a glass with a monotonously changing profile, local shaping of the peripheral part is possible using one roller or one roller and a mandrel. Moreover, in some cases, the mandrel can be structurally designed in such a way that it does not repeat the inner profile of the peripheral part of the workpiece, but has dimensions sufficient to fix the workpiece and to maintain the formed cantilever part of the workpiece and prevent its warping. Therefore, it is carried out structurally with an outer diameter equal to the minimum inner diameter of the peripheral part.

 When manufacturing parts of large diameters with a developed peripheral part, it is recommended that the peripheral part is formed locally using two rollers located on different sides of the formed wall, or at the previous transition using a roller and a mandrel.

 It is advisable to manufacture parts with a bilateral, relatively central, peripheral part by local shaping of its peripheral part simultaneously by two rollers with their movement in opposite directions from the central part. Using this technique can significantly improve the performance of the process. Or, it is possible to conduct local shaping of the peripheral part sequentially with one roller using the reverse of its movement. The choice of one of the two indicated techniques is determined both by the economic feasibility of their application, and by the form of the resulting part.

 With local shaping of parts made of heat-resistant alloys in order to increase tool life and rigidity of the mandrel, it is possible to reinforce them. However, as a result of this, there may be a temperature difference between the preform heated to the deformation temperature and the less heated roller and mandrel. Therefore, in such cases, it is necessary to maintain the heating temperature on the deformable surface of the peripheral part in the range from the deformation temperature to a temperature exceeding the lower temperature threshold of superplasticity for fine-grained material. Otherwise, at a given strain rate, the superficial surface layers will deform under non-optimal conditions of superplasticity. As a result of this, after local shaping in the surface layers of the peripheral part of the part, riveting will take place. At the final heat treatment of such a part in order to enlarge it by 1-2 orders of grain size, there will be a development of zonal heterogeneity, which sharply worsens the mechanical properties of the finished part.

 It is known that during the deformation of a workpiece, especially from nickel alloys, even under the most favorable conditions during stress relaxation, residual stresses associated with a change in geometry that do not affect the forming process of a part can remain, but with subsequent high-temperature heating can lead to the development of zonal grain size distribution. In order to completely eliminate residual stresses and to exclude the possibility of development of heterogeneity after forming parts from nickel alloys, it is recommended to pre-heat from the aging temperature of the alloy to a temperature below the temperature of complete dissolution of the hardening phase and holding for 1-24 hours.

 To obtain parts with maximum accuracy and stability in the shape and dimensions of the part, it is also recommended that the final transition of the final shaping of the peripheral part be combined with the calibration operation, which is carried out at a temperature of deformation with the introduction of rollers into the part, by an amount not exceeding the tolerance on the dimensions of the finished part.

 In FIG. 1 shows a diagram of a device designed to implement the method.

 In FIG. 2-11 shows the types of parts that allows you to get the proposed method.

 In FIG. 12 shows photographs of parts whose types are presented respectively in FIGS. 3,7,9.

 In FIG. 13 is a photograph of a part of the type shown in FIG. eleven.

 On Fig shows a photograph showing the moment of completion of the technological process of manufacturing parts (the upper part of the furnace is removed).

 In FIG. 15 is a photograph showing directly the working area during the manufacturing process of the part (the upper part of the furnace is removed).

 In FIG. 16 is a flowchart illustrating a predominantly first shaping operation of a glass type part using a single roller and mandrel.

 The dotted line shows the initial profile of the peripheral part of the part and the initial position of the roller.

 On Fig shows a diagram of the final operation of forming parts like glass with a monotonously changing profile using a single roller.

 The dotted line shows the initial position of the roller.

 On Fig shows a diagram of the formation of the details of the type of glass with a monotonically changing conical profile using a single roller and mandrel.

 The dotted line shows the initial position of the roller.

 In FIG. 19 shows a sketch of a part after shaping with a collapsible mandrel.

 On Fig shows a diagram of the operation of forming the flange in the peripheral part of the details of the type glass with a monotonously changing profile using a single roller and collapsible mandrel. The dotted line shows the initial position of the roller.

 On Fig shows a diagram of the operation of forming parts with bilateral relative to the Central peripheral part with a monotonously changing profile using a single roller and collapsible mandrels. The dotted line shows the initial position of the roller.

 In FIG. 22 is a flowchart of a glass-type shaping operation with a monotonously varying profile using an external mandrel and one roller. The dotted line shows the initial position of the roller.

 In FIG. 23 is a flowchart of a glass-type shaping operation with a monotonously varying profile using rollers located on opposite sides of the peripheral part.

 16-23, reference numeral 5 shows the blank. Position 11 shows the roller, and positions 19 show the whole, and positions 20,21 and 22 of the collapsible mandrel.

 The curved arrows in FIGS. 16-22 show the rotation directions of the workpiece and rollers.

Examples of the method
The device for implementing the method (Fig. 1) contains fixing units 1 and 2, which are coaxial and equipped with drives (not shown in Fig. 1) for their relative axial movement along the guides 3 and 4, made on the frame (in Fig. 1 not shown ), and rotation of the workpiece 5, including reverse. The fixing nodes are connected by a shaft 6 with bushings 7 mounted on it, by means of which torque is transmitted to the workpiece 3. A carriage 8 is also installed on the bed, equipped with a drive (shown in Fig. 1) for its movement along the guide 9 of the bed, i.e. along the axis of rotation of the workpiece. A roller holder 10 with a roller 11 is mounted on the carriage 8. Drives for moving the roller in FIG. 1 are not shown. Position 12 shows a high-temperature furnace for heating and maintaining a predetermined temperature in the workpiece during deformation. The furnace is equipped with a movable shutter 13 with a hole 14 for inputting a roller. The furnace also has openings 15 and 16 for introducing parts of the fixing units 1 and 2. The roller holder 10 is equipped with a heat shield 17. The device is also additionally equipped with a separate chamber 18 with the possibility of placing the tool in the inoperative position and preheating.

 For shaping the workpiece 3, shown in figure 1, the device further comprises a mandrel 19, 20.

Example 1. The task was to obtain a glass type part with a two-sided tapering profile of the peripheral part made of titanium alloy BT25 (Ti-6.5Al-4Zr-2Mo-l, 5Sn-lW) tapering from the central part. Local shaping was carried out using a profiled blank having a central and peripheral part in the form of a bilateral protrusion. A workpiece with an outer diameter of 450 mm and a thickness of one protrusion of 25 mm and another protrusion of 30 mm was obtained by stamping, and a uniform globular microcrystalline micro-duplex structure (5 μm) was formed in it. A cylindrical billet cut from a casting with a diameter of 390 mm was used as the initial stamping. A blank with a cast structure was subjected to multistage deformation with a rotation direction of rotation of 90 ^° in a two-phase region on a press with a force of 1600 tf under quasi-isothermal conditions. As a result of this treatment, a microcrystalline structure was formed in the deposited washer, which was then deformed using an isothermal die block at 950 ^° C. Before local shaping, the stamping was subjected to rough machining in order to remove the oxidized layer and make a centering hole.

 A schematic diagram of the formation of a glass-type part with a two-sided tapering conical profile of the peripheral part of titanium alloy VT25 tapering from the central part is shown in FIG. 3.

Local shaping of the part was carried out in the device, the circuit diagram of which is shown in figure 1. The workpiece, together with the mandrels, was fixed in the fixing unit. Then the furnace was closed and the furnace was heated to a deformation temperature (950 ^° C). At the same time, through the bushings mounted on the shaft of the workpiece fixation unit, the workpiece was rotated to ensure its uniform heating. The first operation of local forming of the peripheral part was carried out using mandrels and one roller made of ZhS6U alloy (Ni-9Cr-10Co-9.7W-5.5Al-2.6Ti-l, 6Mol, lV). The heating temperature of the workpiece and mandrels in the working furnace was 950 ^o C. The roller was heated in the preheating chamber to a temperature of 100-200 ^o C below that indicated. The roller was introduced into the working furnace together with the roller holder through a window made in the movable wall of the furnace. In this case, the attachment point of the roller to the roller holder was stimulated by means of compressed air passing through the channels made in the roller holder. Local shaping was carried out in several operations using a single roller and mandrel. The rotation period of the workpiece relative to the roller was 25 s.

 In the first operation, the first protrusion was localized to a cylindrical glass type profile. In the first pass, the thickness of the first protrusion was reduced from 25 mm to 15 mm. In a similar manner, the second protrusion was locally formed in two transitions up to a thickness of 12 mm using the reverse movement of the roller. In this case, another mandrel was used, since the inner diameter of the second protrusion is slightly smaller than the second.

 Then, the cylindrical mandrels were replaced with collapsible mandrels corresponding to the internal profile of the peripheral part, and the walls of the cups obtained in the first operation were locally formed using two tools: collapsible mandrels and a roller according to the temperature and speed regimes indicated above. First, the final shaping of the first protrusion was performed, and then using the same roller, the second protrusion.

 A photograph of the finished part is shown in Fig. 12. As seen in FIG. 12, the macrostructure of the part immediately after the final shaping is uniform fine-grained over the entire section of the part.

 Example 2. For shaping a glass-like part with a two-sided tapering conical profile of the peripheral part made of titanium alloy VT25, the same workpiece and the same deformation modes were used as in example 1.

 The operation of local shaping was carried out as follows.

 Two rollers and two mandrels were used. In the first operation, the local projection of the protrusions into a cylindrical glass type was carried out with the simultaneous introduction of rollers and their movement in opposite directions from the central part of the workpiece. In the second operation using collapsible mandrels, the final local shaping of the projections of the part was carried out simultaneously by two rollers.

 As a result, a part was obtained that was similar in shape and structure, as in example 1.

 Example 3. The task was to obtain a glass type part with a one-sided tapering profile of the peripheral part of VT25 titanium alloy tapering in the direction from the central part. Local shaping was carried out using a profiled blank having a central and peripheral part in the form of a one-sided protrusion. Billets with an outer diameter of 450 mm and a protrusion thickness of 25 mm were obtained by stamping, and a uniform globular microcrystalline micro-duplex structure (5 μm) was formed in it. The modes of preparation of the structure and final shaping are similar, as in example 1.

 A shaping diagram of a glass-type part with a one-sided tapering conical profile of the peripheral part of the titanium alloy VT25 tapering from the central part is shown in Fig. 7.

 The operation of local shaping was carried out as follows. In the first operation, shaping was carried out using one roller and a mandrel, in the second operation, only the roller was used.

 The final stage of local shaping was combined with the calibration operation. In this case, a run was carried out along the profile of the peripheral part of the disk with specific forces in the contact spot, causing plastic deformation of the workpiece with a value not exceeding the tolerance limits according to the drawing. Such an operation made it possible to stabilize the size and shape of the finished part and contributed to the almost complete relaxation of residual stresses in it.

 Example 4. The first operation of local shaping of the part was carried out in a similar manner as in example 3. At the same time, the second operation was carried out using a collapsible mandrel and a roller. The disk shaping diagram of this embodiment is shown in Fig. 18.

 Example 5. The first operation of local forming of the part was carried out in a similar manner as in example 3. The second operation was carried out using a mandrel with an outer diameter equal to the minimum inner diameter of the peripheral part.

 As a result of processing for all three options (examples 3, 4, 5), disks with a homogeneous microcrystalline structure were completely manufactured that completely meet the shape and size requirements of the drawing.

 Example 6. The task was to obtain parts from titanium alloy VT25 type glass with a one-sided expanding in the direction from the Central part of the conical profile of the peripheral part. The first operation of local shaping was carried out using a single roller and an inner mandrel in the same manner as in Example 3. After the first operation, the thickness of the peripheral part was 12 mm. Then they changed the inner mandrel to the outer. At the same time, the roller was replaced, and the angle of its inclination relative to the axis of rotation of the workpiece was changed so that it was possible to carry out local shaping of the inner surface of the peripheral part.

 As a result of processing according to this option, it was possible to obtain a part with developed internal and external surfaces of the peripheral part of the part.

 Example 7. The task was to obtain a part similar to that in Example 6. The first local shaping operation was carried out in the same manner as in Example 6. In contrast to Example 6, the second local shaping operation was carried out by two rollers that were located on different sides of the formed walls of the peripheral part. As a result of processing according to this option, it was possible to obtain a part with a developed inner surface of the peripheral part.

 Example 8. The task was to obtain a glass-like part with a one-sided tapering conical profile of the peripheral part of VT25 titanium alloy with the initial coarse-grained structure.

Local shaping was carried out using a profiled blank having a central and peripheral part in the form of a one-sided protrusion. A workpiece with an outer diameter of 450 mm and a protrusion thickness of 50 mm was obtained by stamping, and a coarse-grained structure with a grain size of 200-500 μm was formed in it. The first operation of local shaping of the peripheral part was carried out using a mandrel and one roller heated in a working furnace to 990-960 ^o C. Local shaping of the peripheral part on a glass-type profile with a constant outer diameter was carried out in three transitions using the reverse movement of the roller. At the first transition, the thickness of the peripheral part decreased to 35 mm. At the second and third transitions, the deformation temperature decreased by 10-20 ^° C. The period of rotation of the workpiece relative to the roller was 100 s at the first transition, at the second and third transitions, respectively, 25 and 10 s. In this case, the thickness of the peripheral part decreased to 25 and 12 mm, respectively. An analysis of the microstructure of the peripheral part of the preform, carried out after the third transition, showed that a microcrystalline structure with a grain size of 5-7 μm was formed in the peripheral part, similar to that in Example 1. Next, cylindrical mandrels were replaced with collapsible mandrels corresponding to the internal profile of the peripheral part, and crimped the walls of the glasses obtained in the first operation to collapsible mandrels in the same modes. First, the mandrel was replaced with a collapsible one and the final shaping of the peripheral part was carried out as in Example 4. The final local shaping was carried out in two transitions, with the rotation period of the workpiece relative to the roller at the first transition being 25 s, and at the second transition 5 sec In the first operation, the rotation period of the workpiece relative to the roller was longer than in the second operation. This is due to the fact that in the coarse-grained state, a longer time is required for stress relaxation than in the fine-grained state. In the latter case, the length of the grain boundaries increases significantly, which contributes to the activation of the process of grain boundary slippage, which contributes to the effective relaxation of stresses during superplastic deformation.

Example 9. The task was to obtain a glass type part with a one-sided tapering conical profile of the peripheral part made of powder nickel alloy EP962 (Ni-13Cr-10, lCo-4,3Mo-3,2Al-2,6Ti-3,4Nb -2.8W). The shape of the finished part and the blank for shaping are similar to that in Example 3. For local shaping, a blank with a microcrystalline microcrystalline structure prepared for superplastic deformation with a grain size of 2-3 μm obtained by powder metallurgy was used. Moreover, its peripheral part is profiled into a glass-like shape with a wall thickness of 12 mm, ready for final local shaping, which was carried out using one roller in the same way as in the second operation in example 3. The heating temperature of the workpiece with the mandrel was 1050 ^o C. Roller used the same as in example 1.

 As a result of processing according to this option, a part with a one-sided tapering profile of the peripheral part from the hardly deformed nickel alloy EP962 tapering in the direction from the central part of the peripheral part was obtained in practically one single operation of local shaping.

 As a result of processing according to this option, the part was obtained in a form similar to that in Example 4.

Example 10. The task was to obtain a part such as a glass from a nickel alloy of composition (Ni-16Cr-13Co-4Mo-4W-2, lAl-3,7Ti) with tapering in the direction from the central conical profile of the peripheral part. Local shaping was carried out using a profiled blank having a central and peripheral part in the form of a one-sided protrusion. A workpiece with an outer diameter of 410 mm and a protrusion thickness of 25 mm was obtained by stamping, and a uniform microcrystalline micro-duplex structure (5 μm) was formed in it. A cylindrical billet cut from a hot-pressed rod with a diameter of 230 mm was used as the initial one for stamping. Stamping was carried out on a press with a force of 1600 tf under quasi-isothermal conditions. The workpiece was heated to a temperature of 1050 ^{o C. the} stamp was heated to 950 ^o C.

The operations of local forming of the peripheral part were carried out using a mandrel and one roller in the same manner as in Example 3. The heating temperature of the workpiece and mandrel in the working furnace was 1050 ^° C. The roller was heated in the preheating chamber to a temperature of 100-200 ^° C lower than indicated. The roller was introduced into the working furnace together with the roller holder, while the attachment point of the roller to the roller holder was reinforced by compressed air passing through the channels made in the roller holder. As a result of local shaping, a part of a given configuration with a thickness of the peripheral part of 12 mm was obtained. An analysis of the microstructure of the peripheral part showed that immediately after rotational extrusion, the microstructure in the peripheral part remained fine-grained with a grain size of ~ 5 μm. In order to eliminate residual internal stresses caused by a change in geometry, the disk was annealed in a two-phase γ + γ′-region according to the regime: heating the disk to 850 ^° C, holding for 1 h, then heating to 950 ^° C, holding for 2 h, raising the temperature to 1050 ^o C, holding for 8 hours. If it is necessary to obtain a coarse-grained structure homogeneous over the entire cross section in the part, then raising the temperature to 1150 ^o C, holding for 2 hours, cooling to room temperature. As a result of such heat treatment, a homogeneous structure with a grain size of 20-30 μm was formed in the peripheral part. Thus, when using a cooled tool, conducting additional regulated annealing in a two-phase γ + γ′-region excludes the possibility of development of different grain size in the peripheral part of the part.

Sources of information
1. US patent 3519503, CL. C 22 F 1/10, 1970.

 2. RF patent 2119842, cl. B 21 K 1/32, C 22 F 1/10, 1998.

 3. O.A. Kaibyshev, Superplasticity of alloys, Intermetallides and Ceramics, Springer Verlag, Berlin (1992).

Claims (26)

1. A method of manufacturing complex axisymmetric parts from difficult to deform multiphase alloys having a central and peripheral, mainly in the form of a rim, parts, including installing a profiled billet with the possibility of fixing and rotation and local shaping of the peripheral part at temperatures above 0.4 melting point, but below the recrystallization temperature at a rate of 10 ^-3 to 10 ² c ^-1 tool by local deformation of a roller having at least three step no freedom, characterized in that the local shaping is carried out by compressing the peripheral part of the profiled workpiece in the direction of its forming by means of at least one roller on the mandrel, which serves simultaneously to fix the central part of the profiled workpiece, while the rotation period of the workpiece relative to the local tool is set not less than the intensive time stress relaxation in deformable areas.  2. The method according to claim 1, characterized in that the local shaping is carried out using a mandrel, the diameter of which corresponds to the inner diameter of the peripheral part of the profiled workpiece, while using a workpiece, at least part of the profiled peripheral part of which has an external diameter exceeding the diameter of the finished part .  3. The method according to claim 1, characterized in that the local shaping is carried out using a mandrel, the diameter of which corresponds to the outer diameter of the profiled workpiece, using a workpiece, at least part of the profiled peripheral part of which has an inner diameter smaller than the diameter of the finished part.  4. The method according to p. 1, characterized in that the rotation period of the billets of aluminum alloys is selected no more than 0.25 s.  5. The method according to p. 1, characterized in that the rotation period of the workpieces of titanium and heat-resistant nickel alloys is selected in the range of 0.25-100 s.  6. The method according to claim 2, characterized in that the rotation period for blanks with a coarse-grained structure is selected within 50-100 s.  7. The method according to claim 2, characterized in that the rotation period for preforms with a fine-grained structure is selected within 10-50 s.  8. The method according to claim 2, characterized in that the rotation period for preforms with a submicrocrystalline structure is selected within 0.25-10 s.  9. The method according to claim 1, characterized in that the local shaping is carried out in one or more operations, the number of which is selected depending on the preliminary profiling of the original workpiece and its structure.  10. The method according to claim 9, characterized in that as the initial take a workpiece with a structure prepared for superplastic deformation, profiled in the form of a glass, and local shaping is performed in one operation.  11. The method according to claim 9, characterized in that the preform is prepared with a structure prepared for superplastic deformation, profiled in the form of a central part and a peripheral protrusion, local shaping is performed in two operations, and in the first operation, a preform is prepared in the form of a glass.  12. The method according to claim 9, characterized in that as the initial take a preform with a coarse-grained structure, profiled in the form of a central part and a peripheral thick-walled protrusion, local shaping is performed in two operations, and in the first operation, a preform is obtained in the form of a glass with peripheral compression parts by 50-75% in temperature and speed conditions of superplasticity.  13. The method according to any one of paragraphs.11 and 12, characterized in that the first shaping operation is carried out in several transitions using the reverse movement of the roller.  14. The method according to claim 11, characterized in that use collapsible mandrel.  15. The method according to any one of claims 1 and 11, characterized in that the temperature on the deforming surfaces of the mandrel is maintained in the temperature range of the superplasticity of the workpiece material.  16. The method according to p. 1, characterized in that upon receipt of the details such as a glass with a monotonously tapering profile, an additional operation of local shaping of the peripheral part of the workpiece using a single roller.  17. The method according to p. 1, characterized in that upon receipt of a glass-like part with a monotonously tapering profile, an additional local shaping operation is performed using one roller and a mandrel with an outer diameter equal to the minimum inner diameter of the peripheral part of the part.  18. The method according to claim 1, characterized in that they perform an additional operation of local shaping of the peripheral part of the workpiece using two rollers located on different sides of the formed wall.  19. The method according to claim 1, characterized in that they perform an additional operation of local shaping of the peripheral part of the workpiece using two rollers located on different sides of the formed wall and the mandrel, moreover, in the first operation using a roller and mandrel, and in the subsequent operation, rollers .  20. The method according to claim 1, characterized in that in the local forming of parts made of heat-resistant nickel alloys, a heating temperature is provided on the deformable surface of the peripheral part of the workpiece in the range from the deformation temperature to a temperature exceeding the lower temperature threshold of superplasticity for fine-grained material.  21. A device for manufacturing complex axisymmetric parts having a central and peripheral, mainly in the form of a rim, parts of hard-deformed multiphase alloys containing axial fixation and rotation of the workpiece, which are equipped with devices for installing mandrels, and at least one roller with a roller holder, a working furnace with holes in the walls to enter part of the fixing unit and the rollers and actuators to ensure rotation and movement of the rollers, characterized in that the walls of the furnace ying the movable portion situated around a hole for inputting a roller movable in the axial direction together with the roller over the entire length predetermined stroke video.  22. The device according to p. 21, characterized in that the fixing unit is equipped with devices for installing collapsible mandrels.  23. The device according to item 21, wherein the fixing unit is provided with a shaft and bushings for transmitting torque to the workpiece.  24. The device according to item 21, wherein the roller holder is additionally equipped with a heat shield.  25. The device according to item 21, wherein the working furnace is additionally equipped with a separate chamber for placing the tool in it and pre-heating it.  26. The device according A.25, characterized in that the chamber is combined with the movable part of the furnace wall.

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