3Pomear A,Aune T K,Hawke D. Metals Handbook[M].Oho:Metals Park,ASM,1987.740.
4Lee S,Lee S H,Kim D H. Effect of Y.Sr and Nd additions on the microstructure and microfracture mechanism of squeezecast AZ91-X magnesium alloy[J].Metallurgical and Materials Transactions A:Physical Metallurgy and Materials Science,1998,(29):1221-1235.