R. Yu. Sukhorukov

Scientific fundamentals of high-efficiency roll forming technology for axially symmetrical parts of a gas-turbine engine rotor of high-temperature alloy

Fundamentals of the roll forming technology for disks of gas-turbine engines under super-plasticity conditions are stated. Because of deep underlying reasons of materials science, the technology provides a high process efficiency, equipment universality, the possibility of obtaining workpiece blanks with a high accuracy approaching that of the final part, and the development of structural states corresponding to the optimum complex of operational properties of parts [1, 2]. It is shown that a substantial role in roll-forming technology is played by superplastic deformation conditions, which, in contrast to the simple isothermal deformation, allow us to obtain in disks, either the homogeneous structure and isotropic properties, or the regulated gradient structure corresponding to actual temperature-force conditions of the operation of different parts of gas-turbine rotor disks.

Specific features of rolling of shaft of gas turbine engine under conditions of superplasticity

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.

Modeling the structure formation during hot deforming the billets of the parts of gas-turbine engines made of heat-resistant nickel alloy

The results of finite-element and physical modeling of deformation heating and structure formation during high-temperature isothermal upset of a cylindrical billet according to various modes (continuous and fractional deformation) have been presented. The results of numerical modeling, which agree with the experimental modeling data, showed that, in order to minimize the deformation heating and formation of a homogeneous ultrafine-grain structure in bulk billets made of heat-resistant alloys, it is purposeful to perform the deformation fractionally (with a single degree no larger than 30–50%), which allows for the deformation rate and performance of post-deformation annealing. The formation of an ultrafine-grain structure in the billets made of nickel alloys (for example, EP742U) guarantees an increase in the quality of ready wares.

Technological features of a process and equipment for superplastic rolling of axially symmetric heat-resistant alloy components of rotors for modern aircraft engines

Scientific bases of a technology for superplastic roll forming of axially symmetric parts of gas turbine engines that are made of heat-resistant alloys are described. It is shown that a formed microcrystal structure allows their deformation under conditions of superplasticity, thereby providing changes in physical and mechanical and processing properties. Parts manufactured by superplastic rolling feature a highly homogeneous microstructure over the entire volume and isotropic mechanical properties or an optimized gradient microstructure allowing for nonuniform temperature and power loading in the process of operation. Technological features of the equipment for superplastic roll forming of discs for motors and requirements for the equipment and the control system are described and methods of calculation of major unit strength are covered.

Physical and numerical modeling of the process of rolling off of a tapered shaft of aviation purpose

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.

Influence of the deformational heat treatment on the structure and mechanical properties of nickel-iron alloy

Results have been presented from comparative studies of the structure, mechanical properties, and fracture surfaces of Inconel 718 nickel-iron alloy with different grain sizes obtained by multiple forging and heat treatment.

The determination of power characteristics of isothermal roll formation of critical parts of gas-turbine engines

One of the most promising methods in manufacturing axisymmetric aircraft parts such as disks or hollow shafts is the isothermal roll formation in the state of superplastic deformation (SPD) on specialized reeling machines. Equipment of this class is designed on the basis of calculating the power characteristics expected from these machines. The procedure is efficiently carried out by mathematical modeling. This paper presents a technique for drawing the finite element model of isothermal roll formation in the state of superplasticity as well as the results of this modeling, exemplified by the manufacture of a disk from BT9 heat-resistant titanium alloy. The suggested technique is used in the development of technology and the design of equipment for rolling axisymmetric parts (disks, hollow shafts) from heat-resistant titanium and nickel alloys.

Constructive-Technological Features of a Rotary Drawing of Geometrically Complex Hollow Shafts for Gas Turbine Engines

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.

Optical system for controlling the profile of a roll-formed gas turbine engine disk

The problem of controlling the parameters of details produced in the rolling of aircraft gas turbine engine disks of titanium alloys is considered in the work. The structure of a rolling process control system is described. The results of experimental studies of a laser system for controlling geometrical parameters of a detail heated in a furnace are given. The possibility of applying the triangulation control method is considered. Advice on the choice of basic parameters of the control system embedded in a mill for rolling gas turbine engine disks is given.