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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.

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.