Grain refinement and plastic formability of Mg-14Li-1Al alloy

Al-5Ti-1B master alloy was added into Mg-14Li-1Al (LA141) alloy and then LA141 sheets were prepared by extrusion and cold rolling. The effect of the addition level of Al-5Ti-1B master alloy on the grain size of LA141 alloy was investigated as well as the effects of the total reduction of cold rolling and the annealing temperature on microstructure, mechanical properties and plastic formability of the LA141 sheets. The results show that the optimal addition level of Al-5Ti-1B master alloy into LA141 alloy is 1.25% (mass fraction) and LA141 alloy has the finest grains. With the increase of the total reduction of cold rolling, the grains of the as-rolled LA141 sheets were flattened gradually. A proper anneal temperature of 200 degrees C is obtained for the cold rolled LA141 sheets. Under this condition, microstructure of the LA141 sheets consists of fine and uniform equiaxed grains and has higher Erichsen cupping index (IE).