Advanced cermets based on titanium carbide (TiC), with a ductile nickel aluminide (Ni_3Al) binder, have shown significant promise for use in a variety of demanding wear environments, due to a combination of high strength and good corrosion behavior. A unique feature of TiC/Ni_3Al cermets is that they show increasing strength from room temperature up to ～1,000°C, while current materials such as tungsten carbide/cobalt (WC/Co) show significant strength degradation above ～500°C. In the present study, aqueous colloidal forming methods have been applied to process TiC preforms. Without a dispersant, the TiC powder used shows an isoelectric point at ～ pH 2.6. The use of an ammonium salt of polymethacrylate (Darvan C) does not significantly alter the isoelectric point. TiC preforms were prepared by slip casting suspensions of up to 50 vol. % solids content. After drying, the TiC based cermets were processed by melt infiltration with the Ni_3Al alloy (IC 50) at 1475°C. NJ_3Al content was varied between 20 and 50 vol. % using this approach, resulting in final densities that exceeded 98 % of theoretical.
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