Effects of Cd addition on microstructure and corrosion resistance of AM50-Y-0.6Sb magnesium alloy

The effects of Cd addition on microstructure and corrosion behavior of as-cast AM50-Y-0.6Sb alloy were studied.The results show that the as-cast microstructure of AM50-Y-0.6Sb alloy consists of α-Mg matrix,β-Mg17Al12,Al2Y and YSb.With the increasing of Cd addition,the microstructure is refined gradually and Cd dissolves into the matrix with no new phase formation.The alloy with 1% Cd has the most fine and uniform grains and precipitates.As the content of Cd increasing,the corrosion rate and corrosion current density of the alloys are decreased,and the corrosion potential shifts to the positive.The alloy with 1% Cd has the best corrosion resistance,and the corrosion rate is only 1.07 mg·cm-2·d-1,which is decreased by 42.5% compared with the alloy without Cd addition.