Kotsiuba V. The improvement of the technology and technological equipment for the manufacture of gas turbine engine parts by the pulsed metal working methods

The presented work is aimed at solving the urgent scientific and technical problem of improving the technology and technological equipment for the manufacture of thin sheet parts of the gas turbine engines by the pulsed method of metal working. The analysis of the experimental and analytical and numerical methods for determining the technological parameters of stamping sheet parts of a complex spatial configuration with the uneven degrees of distribution along the perimeter has been given. The reason for the loss of the operational characteristics and the destruction of the forming surface of the die for the stamping by explosion has been established. The urgency of the research on improving the methods for predicting the dynamic behavior of the thin-walled parts with a variable taper angle and an uneven degree of expansion along the perimeter in which the upper and the 29 lower contour are described by various geometric contours has been substantiated. The elimination of the irreversible deformations of the die material for the explosive stamping is no less urgent. With the use of the morphological analysis and mathematical modeling of the process of the pulsed loading and elastic-plastic deformation of the die material, an effective method of hardening and stabilizing treatment of the forming surface of the die has been determined. The development of the phenomenological fracture criteria which predict discontinuity of materials has been given. The limiting deformations of blanks and technological equipment have been determined. The numerical method of calculation in the Ansys AutoDYN system has been refined and expanded by introducing a universal iterative procedure for correcting the pulsed loading of materials when determining the dynamic behavior of the material, which made it possible to determine the optimal location of the explosive charge, the loading parameters of the workpiece material, taking into account its resistance to deformation. The optimal solution is obtained with the alternative options for determining the stability of the die by the linear programming methods with restrictions on hardness, elastic deformations of its material, the occurrence of cracks and chips. This made it possible to determine the parameters of the hardening-stabilizing explosion treatment and mathematical modeling of this process and the process of the dynamic behavior of the workpiece during the explosive stamping. By analyzing the results of the experiments and developing technologies for the explosive stamping of parts with a complex curvature surface, the dependence of the dynamism coefficient of the stress state indicator under a high-speed deformation has been established. A technology and die tooling have been developed for the explosion stamping of parts of a complex simple differential-wall configuration with an uneven degree of expansion along the perimeter.