Effect of addition of Al-Si eutectic alloy on microstructure and mechanical properties of Mg-12wtLi alloy

摘要

Mg-12 Li, Mg-12 Li-3(Al-Si), Mg-12 Li-7(Al-Si) and Mg-12 Li-9(Al-Si) alloys(all in wt%) were fabricated by high frequency vacuum induction melting in a water cooled copper crucible. After subsequently hotrolling and annealing, their microstructure and mechanical properties were investigated. Experimental results show that mechanical properties of Mg-12 Li alloy were significantly improved by the addition of Al-Si eutectic alloy. Mg-12 Li-7(Al-Si) alloy shows the highest strength of 196 MPa of the investigated alloys, which is about 1.8 times of the strength of Mg-12 Li alloy, and maintains high elongation of 27%.The improved mechanical property with addition of Al and Si in the eutectic proportion into Mg-12 Li alloy was attributed to the solution strengthening effect of A1 and precipitation hardening effect from AlLi and Mg_2 Si precipitates.