Studying of accumulation damages regularities under low cycle loading and cycle variable parameters conditions

Abstract

Abstract The aim of the work is to study the possibilities of predicting cyclic durability in low-cycle fatigue and variable cycle parameters conditions, which combination describes the change complex nature in the stress-strain state over time of aircraft engine parts, based on linear and nonlinear models of damage accumulation. To do this, low-cycle fatigue tests of cylindrical samples were carried out for various loading forms, consisting of several simple-shape cycles. On the results of the tests carried out, fatigue life was predicted based on the nonlinear hypothesis of the Marco-Starkey damage accumulation. An analysis of the mechanical hysteresis loops was carried out to estimate the reasons for the increase of life during tests with a large number of groups in blocks.