Effect of Y on microstructure and high temperature properties of wire-arc-additive-manufactured Al–Cu alloy deposits

Abstract

Al–Cu alloy and Al–Cu–Y alloy deposits were formed by wire arc additive manufacturing (WAAM). Through metallography, SEM, EDS and tensile test in high temperature, the microstructure and mechanical properties in high temperature of the alloy accumulator were investigated. So as to investigate the effect of Y on the high temperature structure and properties of Al–Cu alloy deposits, the deposits were kept at 200 °C for 30 min. The results show that the addition of Y to the WAAM Al–Cu alloy deposit can significantly refine grain size, change the growth direction of the primary θ phase, increase the size of primary θ phase. More undissolved θ phases were nailed to the grain boundary after solution treatment, improved the yield strength of the accumulation. The addition of Y to Al–Cu alloy has no effect on strengthening phases in T6 state and the transformation of θ' strengthening phase at high temperature.