Effects of Er , Sc Addition on Microstructure and Properties of WAAM Al-7Si-0.6Mg Alloy

Abstract:

The effects of Er and Sc addition on the microstructure and properties of Al-7Si-0.6Mg fabricated alloy by wire arc additive manufacturing (WAAM) were studied by metallographic microscope, scanning electron microscope, room temperature and high temperature tensile tests. The results show that the addition of Er leads to the shortening of the dendrites and the thinning of the dendrites in the as-deposited alloy, and the addition of Sc leads to the shortening of the size of the α-Al dendrites of the as-deposited alloy, which tends to be equiaxed. After T6 heat treatment , the microstructure differences were eliminated. The addition of Er , Sc can improve the high temperature performance stability of WAAM Al-7Si-0.6Mg alloys at 200℃ and 250℃, and the effect of Sc is better than that of Er.