Effect of twinning and precipitation on low-cycle fatigue damage behaviour of extruded AZ80 magnesium alloy

In this paper, the fatigue behaviour and failure mechanisms of extruded AZ80 magnesium alloy samples were studied with different initial structures. The results show that the twinning-twinning behavior was inhibited to a certain extent by fine grain and precipitates, but the initiation of fatigue cracks was promoted. Studies of the fatigue life and fracture mechanism show that both residual twins and precipitated phases can cause fatigue crack initiation, but less fatigue damage is caused by the twin-induced cracks than by second phase-induced.