制备工艺对原位合成Al_3Ti/Al复合材料显微组织的影响

Effects of fabrication process on the microstructure of in-situ Al_3Ti/Al composites

以工业钛剂和纯铝为反应物,采用熔体反应法原位合成了Al3Ti/Al复合材料,并采用XRD、SEM、EDS等手段研究了反应温度、稀土元素Ce、浇注温度等制备工艺因数对增强相Al3Ti形貌及尺寸的影响,探讨了相应的影响机制。结果表明,随着反应温度升高,Ti原子溶解扩散越快,Al3Ti分布更均匀;提高浇注温度和加入Ce后,Al3Ti相变得更加细小。其中,900℃时在铝熔体中加入占其质量分数0.3%的Ce并加入钛剂,反应完全后在900℃浇注,生成的Al3Ti相呈短棒状或块状,长度尺寸在10μm左右,且均匀分布于铝基体中。

In-situ AlaTi/AI composites were fabricated by direct melt reaction method in AI-Ti system. lhe effects of fabrication process on microstructure of the in-situ A13 Ti/A1 composites with different fabrication pa- rameters such as reaction temperature, rare earth element Ce and casting temperature were investigated by XRD,SEM and EDS. The variation of the shape and size of A13Ti phase and the mechanism were studied in the present paper. The results showed that the higher reaction temperature, the faster A13 Ti grow up and more hom- ogeneous. The size of A13Ti become smaller as the casting temperature decline and after adding Ce. When the parameters for fabricating AI3 Ti/A1 composites are that reaction temperature is 900℃ and casting temperature is 900℃. The reinforced particles are approximately 10μm and the morphology of reinforced particles is small blocky or short rod-like. The in-situ formed A13Ti particulates are homogeneous dispersion in the centres of A1 grain.