Effects of the aging state and tensile strength on the fatigue properties of 6A01 aluminum alloy

Abstract

To study the effects of the aging state and tensile strength on the fatigue properties of 6A01 Al alloy, the high-cycle fatigue (HCF) experiments were carried out for different aging states. The results show that the 6A01 Al alloy with the highest tensile strength at peak-aging state can exhibit the highest fatigue strength in comparison with the overaged state and the underaged state. The main reason is that the increased strength of the 6A01 Al alloy at peak-aging state can improve the plastic deformation resistance and inhibit the fatigue crack initiation. Besides, the intermittent distribution of grain boundary precipitates at the peak-aging state is beneficial for reducing the fatigue damage. From these results, it is verified that the tensile strength plays a key role in the fatigue strength relative to the aging state for the low-strength Al alloys.