Influence of γ→α' Transformation on Low-cycle Fatigue Behavior in Austenitic Stainless Steels

Abstract

In this paper, the influence of γ→α' transformation on strain-controlled low cycle fatigue behavior of austenitic stainless steels was studied in the temperature range from room temperature to -162°C. Low cycle fatigue life of stable steel was longer than that of unstable one. In unstable steels, fatigue life decreased with increase of volume of α'-phase induced in cycling test.
A discussion was made on cyclic hardening behavior by γ→α'transformation. It was shown that harmful effect of α'-inducement on low cycle fatigue life was attributed to strengthen cyclic hardening and fatigue life was represented as a function of amount of cyclic hardening.