Reaction behaviors occurring in Ti/Al foil metallurgy

Reaction behaviors occurring in Ti/Al foil metallurgy were systematically investigated. Particular emphasis was focused on the reaction between solid Al and Ti as well as subsequent reaction between TiAl3 and Ti layer. In the solid reaction between Al and Ti, the presence of residual Al is mainly caused by inhomogeneous growth of TiAl3 layer and micro-voids existing at the interface. However, through reaction between molten Al and Ti, TiAl3/Ti multilayer can be achieved with complete consumption of Al. During subsequent high-temperature heat treatment, TiAl3/Ti multilayer will eventually turn into Ti3Al/TiAl multilayer accompanying with simultaneous formation and successive disappearance of intermediate phases, such as TiAl2 and Ti2Al5. Moreover, it is found that the growth direction of TiAl layer changes as a function of annealing time between different couples in multi-intermetallics system.