Effect of La on microstructure and properties of AZ61 magnesium alloy

The effect of adding La with(0~1.5)% on microstructure and mechanical properties of AZ61 magnesium alloy was investigated.The results show that addition of 0.5%~1.5% La can refine the phase of β-Mg17Al12 in the cast AZ61 magnesium alloys and form the needle-like phase of Al11La3 in the matrix;The needle-like phase of Al11La3 starts to coarsen and grow up and the phase of β-Mg17Al12's network structure begin to separate and refine when the content of La exceed 1.0%;The addition of La can improve the mechanical properties of AZ61 magnesium alloys,when the content of La up to 1.0%,the mechanical properties of AZ61 magnesium alloy is best.Therefore,The best value of micro-alloying is the mass fraction of La in AZ61 magnesium alloys reaches to 1.0%.