Effect of size and distribution of titanium carbide
on microstructure and mechanical properties of
Ti-25V-15Cr-2Al-0.2C-0.2Si alloy
on microstructure and mechanical properties of
Ti-25V-15Cr-2Al-0.2C-0.2Si alloy
(1. Laboratory of Titanium Alloys, Beijing Institute of Aeronautical Materials,
Beijing 100095, China;
2. Rolls-Royce Plc, P.O. Box 31, Derby DE24 8BJ, U.K.)
Beijing 100095, China;
2. Rolls-Royce Plc, P.O. Box 31, Derby DE24 8BJ, U.K.)
Abstract: The effect of size and distribution of titanium carbide on the microstructure and mechanical properties of non-burning β titanium alloy Ti-25V-15Cr-2Al-0.2C-0.2Si (mass fraction, %) was investigated. The microstructure of the heat-treated and exposed alloy was studied using optical microscopy(OM), scanning electron microscopy(SEM) and transmission electron microscopy(TEM). It is found that carbides with finer size and more uniform distribution can suppress the formation of α precipitates more effectively, and can especially decrease the amount of grain boundary α precipitates after long-term exposure at 540℃ (the expected application temperature). Thus, significant improvement in thermal stability can be achieved by refining carbide particles in the matrix of the alloy.
Key words: non-burning; titanium alloy; carbide; mechanical properties