Microstructure and Mechanical Properties of Ti-Cu-Based Materials Produced by Using Reactive Melt Infiltration and Liquid Phase Sintering Techniques

In the present study, Ti-Cu-based alloys were provided by the simultaneous application of both reactive melt infiltration and liquid phase sintering techniques. In order to apply the reactive melt infiltration technique, stearic acid was added at 10, 15, and 20% by weight as the pore forming agent in titanium. Cold-pressed samples were subjected to two different sintering temperatures (1100 and 1200 °C), and melt copper was provided to leak between the titanium particles, natural pores, and the pores forming upon the vaporization of stearic acid. According to the microstructure results, two types of microstructure (eutectoid and hypereutectoid) formed. Eutectoid structure consists of formation of α-Ti + Ti2Cu. The presence of Ti2Cu intermetallic phase caused an increase in hardness. While the increase in the sintering temperature increased transverse rupture strength, the increased amount of copper caused a decrease due to pore formation (natural pores and pores produced). According to the morphology of the surface of fracture, brittle transgranular and partially ductile fractures occurred in the samples. In summary, it was found that 20% Cu amount and 1200 °C were the most suitable in terms of hardness and relative density, while pure titanium had the highest TRS value at 1200 °C.