Fabrication of NiAl and TiC intermetallic matrix composite coatings

In this work, the intermetallic matrix composite coatings of the TiC-Ti2Ni-Ti3Al system were investigated. Induction heating was used to initiate the self-propagation high-temperature synthesis (SHS) reaction of the multilayer systems of Ti/C-Ni/Al-Ti on the steel substrate. The role of Ni/Al reaction on the SHS process of Ti/C-Ni/Al-Ti was compared to that of Ni/Al-Ti. The results showed that the TiC composite system was composed of TiC dispersed in the intermetallic Ti-Al and Ti-Al systems. This indicates that high exothermic reaction of the SHS process of Ni/Al initiated the subsequent reactions in the Ti-Al, Ti-Ni, and Ti-C systems. The Ti3Al-Ti2Ni multiphase system was formed due to the interaction between the liquid product of NiAl and Ti. Surprisingly, NiAl was disappeared in the Ti/C-Ni/Al-Ti system. This work improves the understanding of the formation mechanism of the NiAl reaction as the agent for the formation of TiC-Ti2Ni-Ti3Al intermetallic matrix composite.