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Results are presented from studying the structure and mechanical properties of an Al–Cu–Al metal-matrix composite obtained via shear under pressure on Bridgman anvils with grooves. The tensile strength is 485 MPa, considerably higher than that of either pure aluminum or copper. The main mechanism of failure is a viscous fracture along the Al matrix with no notable stratification along the interphase boundaries.

A method of surgical treatment of midshaft clavicular fractures and a compression interlocking nail for osteosyn-thesis of the clavicle were developed. Strength characteristics of various bone−implant−bone systems in osteosyn-thesis of midshaft clavicular fractures were compared. It was shown that none of the tested fixation techniques provides stability under conditions of axial loading comparable to that of an intact clavicle. The developed design can be recommended as a method of choice for osteosyn-thesis of midshaft clavicular fractures, as it demonstrated strength characteristics comparable to those of other systems.

For manufacturing thin-walled shafts for gas turbine engines of heat-resistant steels and alloys, the labor-intensive multistage drawing of a sheet of the workpiece in dies is used. The following problem is posed in the work: to study the possibility of manufacturing such parts by a less labor-intensive method: the rotary drawing of a thick-walled workpiece (sheet) by a spinning lathe by rolling a roll under hot deformation conditions. For this purpose, the computer and physical modeling of the rolling process of hollow shafts of a thick-sheet steel workpiece was carried out. The important parameters of the technological process of manufacturing a geometrically complex shaft are determined: the initial workpiece shape and the changes in its shape when rolled on a mandrel mounted on the spindle of the spinning lathe of the PNC 600 type. The research results are used for rolling full-size shafts of chromium steel of the EI962-Sh grade.

The plastic behavior during deformation by upsetting and its effect on the microstructure in the polycrystalline Ni2.19Fe0.04Mn0.77Ga alloy are studied. The temperatures of martensitic and magnetic phase transformations were determined by the method for analyzing the temperature dependence of the specific magnetization as M F = 320 K, A S = 360 K, and T C = 380 K. Using differential scanning calorimetry, it is shown that the phase transition from the ordered phase L21 to the disordered phase B2 is observed in the alloy during sample heating in the temperature range of 930–1070 K. The melting temperature is 1426 K. An analysis of the load curves constructed for sample deposition at temperatures of 773, 873, and 973 K shows that the behavior of the stress–strain curve at a temperature of 773 K is inherent to cold deformation. The behavior of the dependences for 873 and 973 K is typical of hot deformation. After deforming the alloy, its microstructure is studied using backscattered scanning electron microscopy. Plastic deformation of the alloy at study temperatures results in grain structure fragmentation in the localized deformation region. At all temperatures, a recrystallized grain structure is observed. It is found that the structure is heterogeneously recrystallized after upsetting at 973 K due to the process intensity at such a high temperature. The alloy microstructure after plastic deformation at a temperature of 873 K is most homogeneous in terms of the average grain size.

Heat-resistant alloys are the basic material of gas turbine engine (GTE) design. Fine-grained structure in these alloys can be formed by isothermal forging and then different axisymmetric GTE components as wheels, shafts, rings can be superplastic roll formed. Examples of the superplastic and isothermal deformation use for manufacturing components out of superalloys and steels for critical applications are given. The possibility of roll forming parts as rings with a diameter up to 800 mm and as flange - cone with a diameter up to 600 mm out of superalloys (Inconel 718, EK79, EP741NP), accordingly, on SRZHD-800 and modified PNC-600 mills were showed. The macrostructure investigations of the components after the roll forming showed that the homogeneous structure was formed. The microstructure at the flange portion was fine-grained and at membrane zone was coarse-grained. Cone part was roll formed at isothermal condition from pre-stamped chromium martensitic steel sheet. Manufacturing technology of roll forming was tested by computer and physical simulation. Service properties of components were obtained by subsequent heat treatment. The effectiveness of the technology associated with increased service properties of components and decreases the labor content by automated equipment.

One of the most promising methods of manufacturing axisymmetric parts of gas turbine engines is local deformation on specialized rolling mills. To design this class of manufacturing operations and equipment, it is effective to use physical and numerical modeling. The article has provided the method and results of physical and numerical finite-element modeling of local deformation process of a detail of a cone-with-cylinder type made of EI962–Sh chromium steel. Analyses of the energy-power parameters of the technical process and the possibility of the destruction of a part during the deformation process have been carried out.

The structure and properties of a polycrystalline Ni–Mn–In Heusler alloy have been studied after a plastic deformation by upsetting. An analysis of points of a martensitic and magnetic phase transformations shows that the martensite transformation takes place at temperatures lower than the Curie point. At high temperatures in the range 930–1110 K the alloy undergoes the phase transformation of ordered phase L21 to disordered phase B2, and the melting temperature of the alloy is 1245 K. The flow curves of the alloy cylindrical samples at temperatures 773, 873, and 973 K have been built. An analysis of the alloy microstructure after upsetting at a temperature of 773 K leads to the conclusion that many macrocracks are initiated in the sample. The treatment at 873 and 973 K causes a fragmentation of the grains with grain sizes from several to several dozen micrometers. However, the upsetting at 873 K leads to insignificant scatter in the grain sizes, and the microstructure is more homogeneous and worked out.

This work is devoted to the specific features of the rolling of hollow shafts made of nickel-base superalloys under conditions of superplasticity. Limitations are mentioned, which hamper the use of the highly efficient multiroller rolling of the shafts made of these alloys under conditions of superplasticity. The tried and tested procedure of rolling hollow shafts, which involves the use of a mandrel and a single roller, is presented. It is shown that the shaping of a shaft using this procedure requires an expanded bulk deformation zone to appear, which propagates over the entire cross section of the blank under the zone of its contact with the roller. The dimensions of the tool that provide the formation of this deformation zone are determined. The possibility of the use of the axisymmetric formulation of the problem on bulk deformation in the course of the rolling of shafts to determine the stress-strain state of the material is substantiated with the help of the Deform-3D applied software package.

One of the most promising methods for manufacture of axially symmetric parts such as disks or hollow shafts of gas turbine engines is local deformation using cold rolling. Physical and mathematical modeling can be quite effective for designing this class of equipment and process operations. This article presents the methodology and results of physical and mathematical finite element modeling of local deformation of parts such as a tapered cylinder fabricated from chromium steel alloy grade 11H11N2V2МF-Sh. Chemical elements in the alloy are designated by the letters which stand for: H – Chromium, N – Nickel, V – tungsten, M – molybdenum, F – vanadium, Sh – electroslag remelting. According to GOST 5632-72 (Russian standard), this type of nickel-chromium alloy consists of about 11 % of chromium, 1.5–2 % of tungsten and nickel, up to 1 % of molybdenum and vanadium, and 0.11 % of carbon, hundredths of one percent of phosphorus and sulfur. It is heat-resistant high-grade steel, which is used for the manufacture of parts operating unloaded at 900–1000 °C. The purpose of the paper is to analyze the process energy-power parameters and possible fracture of parts during deformation.

Commercially pure (99.9%) copper was severe plastically deformed by equal-channel angular pressing (ECAP) following route-Bc in three different processing regimes in order to obtain ultrafine-grained (UFG) microstructures leading to improved mechanical properties. In regime-1, the billets were processed at room temperature up to eight passes. The billets were processed at 200 degrees C up to eight passes in regime-2. Regime-3 is a hybrid regime by which the billets were deformed at 200 degrees C up to four passes first, and these billets were then processed at room temperature for one, two and four passes. In all regimes, the ECAP processing results in a refinement of the conventionally grained (CG) initial microstructure of copper down to sub-micron level leading to a great improvement in the strength as compared to CG copper. Among the regimes applied, regime-3 was found to be the best regime for improvement in strength along with adequate ductility. The samples showed more than eight times increases in yield strength after processing in regime-3 for 4 + 4 passes, from 47 MPa for CG copper to about 408 MPa for the UFG sample. Such improvement in strength was accompanied by a 16.9% total elongation and 6% uniform elongation. The processing in regime-2 resulted in the best elongation to failure of about 22% after eight passes, but it gave the lowest strength values among others.