Effect of heating temperature and cooling rate on the microstructure and mechanical properties of a Mo-rich two phase α plus β titanium alloy

In this work, influence of heating temperature and cooling rate on microstructure and mechanical properties of a Ti-6Al-1V-4Mo-Si alloy was investigated. The samples were heated to beta (1020 degrees C) and alpha + beta (950 degrees C and 850 degrees C) phase field followed by furnace cooling, air cooling and oil quenching. Basketweave morphology was witnessed for samples furnace cooled from beta phase field, while Widmanstatten microstructure was observed for most air-cooled samples. For samples oil quenched from beta phase field, HCP martensite (alpha') was formed, while for samples heated in alpha + beta phase field, lamellar alpha with alpha ' was observed. Oil quenching from the beta phase field resulted in high strength and low elongation. The strength decreased and elongation increased with reduction in the heating temperature. Highest elongation (similar to 16%) was obtained for samples heated to 850 degrees C followed by furnace cooling. The elastic modulus displayed a wide range of values (70-150 GPa) depending on the processing conditions.

Automated summary

The study examined the influence of heating temperature and cooling rate on the microstructure and mechanical properties of a Ti-6Al-1V-4Mo-Si alloy. Different processing conditions resulted in varying microstructures, with oil quenching from the beta phase field leading to high strength and low elongation. The elongation increased with decreasing heating temperature, with the highest elongation obtained from samples heated to 850 degrees C followed by furnace cooling.