【摘要】 采用重力铸造制备了Mg-9Li-xAl(Al的质量分数x为0,3%,6%,9%)合金。试验研究了不同铝含量的Mg-9Li-xAl合金的组织和力学性能。结果表明,铝的质量分数x对Mg-9Li-xAl合金中的晶粒大小及晶粒分布有很大影响。当w(Al)=6%时,大量的小块状AlLi相出现在合金中并均匀地分布在β-Li基体上。当铝含量过多时,AlLi会由小块状转变为片状贯穿分布在β-Li基体上。合金的强度随着铝含量的增加先增加后降低,伸长率随着铝含量的增加而逐渐降低。当w(Al)=6%时,其强度到达最大,屈服强度和抗拉强度分别达到了136.8 N/mm~2和186.5N/mm~2。更多还原

【Abstract】 As-cast Mg-9Li-xAl( x = 0,3,6,9 wt%) alloys were prepared with the gravity casting method,to investigate how Al element influences the microstructure and properties of Mg-9Li-xAl alloys. The results show that the aluminum content has a significant influence on the grain size and grain distribution of as-cast Mg-9Li-xAl alloys. When w( Al) = 6%,a great quantity of small blocky new phases AlLi appear in the alloy,homogeneously distribut in the matrix of β-Li. When the content of Al increases more than expected,small blocky AlLi will convert into the lamellar type. Alloy strength increases firstly and then decreases with the increase of Al content while alloy elongation decreases gradually. When w( Al) = 6%,its strength reaches the maximum,the tensile strength and yield strength reach 186. 5 N/mm~2 and 136. 8 N/mm~2,respectively.更多还原