On plastic deformation and fatigue under multiaxial loading Original Research Article

This paper presents an experimental and theoretical investigation of deformation and fatigue behaviour under multiaxial random loading. The inelastic stress-strain response under complex loading paths has been predicted using an incremental plasticity model, which incorporates a memory rule to account for the variable-amplitude and non-proportional loading effects. Based on hysteresis strain-hardening behaviour and the history described by the memory effect under multiaxial loading, a mechanics-based cycle counting method has also been proposed for multiaxial random loading. The evaluation of cumulative damage by the cycle counting method combined with Minerʹs linear rule and a strain-path-dependent fatigue damage parameter is compared with experimental results of two metals under biaxial variable-amplitude loading.