摘要
采用XD法原位合成TiCp/Al预制块,并通过XRD、SEM、EDAX和DTA等手段研究了预制块的组织和性能,探讨了TiCp/Al预制块在镁液中的熔化行为。结果表明:TiCp/Al预制块中,基体Al的熔点约为635.7℃,略低于纯铝的熔点,但TiC粒子之间存在较强的结合力,使其在高温加热时仍能保持原有形状;未搅拌时,TiCp/Al预制块在800℃的镁液中保温60min后仍不熔化,采用搅拌工艺有利于促进TiCp/Al预制块的熔化,并且使TiC粒子在熔体中均匀分布。TiCp/Al预制块在镁液中熔化时,基体Al通过熔化和对流扩散进入到镁液中,TiC粒子间的较强的结合力需通过搅拌产生的剪切力才能破坏,并随镁液流动进入到镁液中。机械搅拌可使TiC粒子在镁液中均匀分布。
TiC_p/Al prefabricating alloy was fabricated by in situ reaction, and its microstructure and mechanical properties were investigated by means of XRD, SEM, EDAX, DTA etc. It is found that the melting point of Al matrix in TiC_p/Al prefabricating alloy is about 635 ℃, which is lower than that of pure Al, but there exists a kind of stronger combinational force between TiC particles, which makes the TiC_p/Al prefabricating alloy keep its shape at high temperature of 800 ℃. The TiC_p/Al prefabricating alloy is melted in molten Mg with different technologies. The results show that the TiC_p/Al prefabricating alloy will not be melted after holding for 60 min at 800 ℃ without mechanical stirring; on the other hand, by means of mechanical stirring it can be melted in molten Mg, and therefore makes TiC distribute uniformly in molten Mg. The melting mechanism of the TiC_p/Al prefabricating alloy in molten Mg can be explained as follows: with the help of shear force of molten alloy flow produced by mechanical stirring, the combinational force between TiC particles will be destroyed, and therefore, the particles can easily distribute uniformly into the molten Mg.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2004年第11期1875-1880,共6页
The Chinese Journal of Nonferrous Metals
基金
福建省自然科学基金资助项目(E0310008)
福建省科技三项费用资助项目(K02019)
