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采用机械活化+热爆法制备AB2型Laves相Mg(Cu1-xAlx)2(0≤x≤0.35),并对热爆产物进行XRD、EPMA、SEM和DSC分析。结果表明:MgCu2中的部分Cu被Al替代,晶体结构并不发生改变,主相是MgCu2型λ1相。随Al替代量的增加,λ1相的点阵常数逐渐增大,整个XRD衍射峰向低角偏移增大,致密度逐渐提高,晶粒尺寸减小,点阵畸变增大。随Al替代量的增加,λ1相的熔点先升后降,当化学计量比为Mg2Cu3Al(x=0.25)时,熔点达最高,约为910℃,比MgCu2的熔点(约797℃)高113℃,说明用轻质、抗氧化性能高的Al元素进行合金化,能够使C15结构的AB2型Laves相的热稳定性提高,其中Mg2Cu3Al是更具开发潜力的化合物。
AB2-type Laves phase Mg (Cu1-xAlx) 2 (0≤x≤0.35) was prepared by mechanical activation and thermal explosion method. The products were analyzed by XRD, EPMA, SEM and DSC. The results show that part of Cu in MgCu2 is replaced by Al, the crystal structure does not change, and the main phase is MgCu2 type λ1 phase. With the increase of Al substitution amount, the lattice constant of λ1 phase increases gradually, the diffraction peak of XRD increases to low angle, the density increases gradually, the grain size decreases and the lattice distortion increases. The melting point of λ1 phase first increases and then decreases with the increase of Al substitution amount. When the stoichiometric ratio is Mg2Cu3Al (x = 0.25), the melting point is the highest, about 910 ℃, which is 113 ℃ higher than the melting point of MgCu2 (about 797 ℃) , Which shows that the alloying of Al element with light weight and high oxidation resistance can improve the thermal stability of AB2 type Laves phase of C15 structure. Among them, Mg2Cu3Al is a more promising compound.