【摘要】 通过SEM和TEM等分析手段,研究了液-固反应制备的Al-Ti-C晶粒细化剂合金的组织特征与细化性能,并结合热力学分析,探讨了液-固反应合成机制。结果表明:Al-Ti-C晶粒细化剂合金组织中TiAl3呈枝晶状,TiC呈颗粒状,TiC为非化学计量比化合物,可表示为TiCx形式,x=0.5~0.8,其晶格常数为0.430~0.433nm,该晶粒细化剂对纯Al具有良好的组织细化作用;液-固反应中,在液-固界面处形成瞬时高温,从而达到Ti、C反应的热力学条件,Al-Ti-C合金的形成符合溶解-析出机制,并由三组基元反应构成。更多还原

【Abstract】 The microstructure characteristics and refining ability of Al-Ti-C master alloy prepared by liquid-solid reaction were investigated by SEM and TEM, and the liquid-solid synthesized mechanism was analyzed from the view of thermo-kinetics also. The results indicate that the microstructure of the Al-Ti-C master alloy is composed of dendritic TiAl₃ phase and particle TiC, where TiC belongs to non-stoichiometric ratio compound in the form of TiC_x, for x of 0.5⁰.8, whose lattice contant is 0.430⁰.433 nm. The master alloy can obviously refine microstructure of the Al alloy, which is resulted from the occurrence of instantaneous high temperature in the interface of liquid-solid meet the thermal-kinetics conditions of Ti and C reaction during liquid-solid reaction. The formation of Al-Ti-C master alloy belongs to the solution-precipitation mechanisms, which consists of three groups of primitive reactions.更多还原