Cyclic Plasticity: Some Properties of the Hysteresis Curve of Structural Metals at Room Temperature

Abstract

The hysteresis curve in the transient and steady-state stage is characterized by inequalities and periodicity conditions for the tangent to the hysteresis curve (dσ/dε) and its derivative (d2 σ/dε2 ). Cyclic creep and cycle dependent stress relaxation are considered. Evidence exists that structural metals have a nonfading memory for two discrete items, the maximum stress amplitude of the cyclic steady state and the sign of dσ during the last unloading. The dσ-part of the memory can be erased by a gradual reduction in amplitude.