Tuning the LPSO-dominated microstructure for strength increment of wire arc-directed energy deposited VWZ104K magnesium alloy

This is the authors' abstract. We don't add key points for this paper.

Long-period stacking ordered (LPSO) phase endows Mg-Gd-Y-Zn-Zr magnesium alloys with improved mechanical property. Here, the Mg-10Gd-4Y-1Zn-0.5Zr (wt.%) alloy is fabricated by wire arc-directed energy deposition (WA-DED), and the microstructure dominated by LPSO phase is tuned for strength improvement. Results show that the original as-deposited alloy contains 18R-LPSO phase, acicular γ'' phase and eutectic phase. After T6 treatment, the eutectic phase disappears, and the 18R-LPSO phase and grains become coarser, with the transformation from acicular γ'' phase into 14H-LPSO phase. Resultantly, due to the significant LPSO-strengthening effect, the yield strength and ultimate tensile strength of the as-deposited alloy were increased by 64.6 % and 36.1 %, respectively. This study provides a remarkable LPSO-strengthening pathway for fabricating high-performance magnesium alloys via WA-DED.