750 Fatigue Properties of Al 7075 Alloy after Hard Rolling

Abstract

A conventional surface strengthening technique, hard rolling, was employed to improve the fatigue properties of A17075. The results show that the fatigue strength of hard-rolled specimens is increased around 70% compared with that of the non-hard-rolled specimens. In agreement with this, the hard-rolled specimens exhibite a much lower fatigue crack growth rate, indicating that after hard rolling, fatigue crack initiation and propagation are obviously delayed. The improvement of fatigue properties is analyzed in terms of the microstructural change and the residual stress induced by hard rolling.