Production of TiB2-TiN composites by combustion synthesis and their properties

The self-propagating high-temperature synthesis (SHS) process has been applied to formation of composites consisting of TiB2 and TiN ceramics synthesized simultaneously, Ti, B, and BN powders were used as raw materials. The SHS reaction was initiated by a tungsten heating coil. XRD experiments confirmed that the reaction was complete, and that only TiB2 and TiN phases were detected. Microstructural observations revealed that both TiN and TIB2 crystal grains had small sizes of less than 1 mu m in the composites with high TiN content. Inhibition of grain growth can be attributed to the pinning effect of TiN grains, Excellent corrosion resistance was obtained for HCl reagent.