Effect of alloying on high temperature fatigue performance of ZL114A (Al-7Si) alloy

The effect of Cu, Fe and Ni on high-temperature mechanical performance and fatigue properties of ZL114A alloy was studied through high temperature fatigue test and SEM. The results show that the three elements have a detrimental influence on high temperature cyclic fatigue life. When the contents (mass fraction) of Fe, Cu and Ni in ZL114A alloy are 0.28%, 1.53% and 0.16%, respectively, the high temperature tensile strength and cyclic fatigue of ZL114A alloy are improved from 194 MPa and 40.2 MPa to 236 MPa and 48.2 MPa by alloying. The main reason that high temperature tensile strength and cyclic fatigue of ZL114A alloy are improved significantly is that the three elements greatly improve the proportion of Cu/Mg in ZL114A alloy and nickel content.