Експериментальне визначення ефекту Баушингера і пошкоджуваності матеріалу

Abstract

Present paper is devoted to an experimental determination of the Bauschinger effect and material damage which occur at elastic-plastic deformation. The series of cyclic tension-compression tests of flat samples made from aluminum alloy D16 were conducted. Given a phenomenon of buckling at compres-sion stage the flat samples were cut according to both ATSM standard and preliminarily conduction of the buckling analysis. Based on the experimental data a mathematical model of plasticity is developed in the way of improvement of the nonlinear kinematic hardening model by introducing of an additional function of previously accumulated plastic strain. For better correlation with experimental results the Mises plasticity criterion written in the form of the Baltov and Sawczuk’s model was modified by intro-ducing of a function which is intended to describe decrease of the yield stress during plastic deforma-tion. In order to model a reduction of the young’s module at unloading stage of the cyclic tension-compression test a material damage parameter was introduced according to the effective stress concep-tion. Numerical simulation of the cyclic tension-compression testing which accompanied experimental investigation has shown good coincidence with experiment results.