Development of titanium metal matrix composites reinforced with coated powders

This paper evaluates the feasibility of using SiC and TiC as reinforcement particulates for titanium metal matrix composites (Ti-MMC). The SiC and TiC particles were coated with titanium using a chemical coating technology in order to achieve a homogeneous mixing when they were mixed with pristine Ti. The Ti-MMC with these specially prepared reinforcements were fabricated by a conventional press and sinter route. The effects of sintering temperature in Ti matrix were investigated with respect to phase constituents, microstructure and tribology properties. No in situ phases were observed during sintering and the reinforcement and matrix show sufficient bonding, which acts as a major parameter to enhance hardness and wear resistance compared to pure Ti. All the composite samples had a high sintered density. The hardness of the composites increased with an increase in the sintering temperature. It was also noticed that with the increase in the temperature ranging from 1200 degrees C to 1300 degrees C, improvement in the mechanical and tribological properties of the developed titanium matrix composites could be observed. The highest hardness value 385 +/- 20 HV1 was recorded for Ti-2 wt.% Ti-coated SiC composite when sintered at 1300 degrees C for 3 h.