An investigation of residual stress relaxation processes which arises in plate circle hole surface layer in vibrocreep conditions

Development and implementation of calculation method of residual stress relaxation in the surface hardened layer of plate hole under vibrocreep conditions with combine static and cyclic loading are presented. Based on the ideas of decomposition and aggregation, the calculation of the kinetics of relaxation of residual stresses in the hole surface layer is reduced to gluing solutions of three boundary value problems. While solving the first boundary value problem the three-dimensional distribution of residual stress fields and plastic strains in hole hardened layer of plate is defined. Solving of the second boundary value problem defines the stress-strain state of a hole hardened layer of plate during vibrocreep without taking into account the surface hardened layer. For the third boundary value problem the relaxation of residual stresses in surface hardening layer, deformable in the “hard” loading at given values of the strain tensor components, which are determined by the second boundary value problem solving, is investigated. The numerical analysis of the cyclic component amplitude value influence on residual stress relaxation process is completed. The numerical analysis presents a residual stress relaxation rate increasing according to cyclic component value.