열간압연으로 제조된 Ti Aluminide 다층판재의 미세조직 1 . 금속간화합물의 생성거동

The objective of this study is to analyze microstructures of multilayered Ti aluminide sheets fabricated by self-propagating high-temperature synthesis(SHS) reaction using hot rolling. Multilayered Ti/Al sheets were prepared by stacking thin Ti and Al sheets alternatively, and had a good Ti/Al interfacial bonding after pre-rolling at 500℃. When these sheets were heat-treated at 1000℃, spheroidal TiAl_3 phases were formed by SHS reaction at Ti/Al interfaces and inside Al layers. This formation continued until Al was completely consumed, and the Ti/Al multilayers turned into the Ti/TiAl_3 multilayers. Microstructural analysis on the hot-rolled, multilayered Ti/TiAl_3 sheets indicated that intermetallic phases such as TiAl_2, TiAl, and Ti_3Al were formed at Ti/TiAl_3 interfaces due to interaction between Ti and TiAl_3, and that pores formed in TiAl_3 layers were significantly reduced during hot rolling. These findings suggested that the SHS reaction using hot rolling was economical and useful for the continuous fabrication of the multilayered Ti/Ti aluminide sheets.