Effect of residual stress induced by cold expansion on fatigue crack growth of Aluminium alloy 2024-T351

Abstract

Fatigue life and fatigue crack growth rate are controlled by stress ratio, stress level, orientation of crack, temper-ature, residual stress, corrosion, etc. The effects of residual stress on fatigue crack growth in aluminium (Al) alloy 2024-T351 by Mode I crack were investigated by applying constant amplitude cycles based on maximum stress intensity factor failure criteria. The residual stress fields induced by cold expansion were imposed on the specimen with double through crack at hole by numerical experimentation. The fatigue crack growth tests were performed in transverse-longitudinal orientation using NASGRO model. The effects of stress ratio and different levels of residual stress fields on fatigue life and fatigue crack growth rates were analyzed. The results showed that compressive residual stress has significant effect on fatigue behavior of Al alloy 2024-T351.