Titanium alloy having good heat resistance and method of producing parts therefrom

A method of producing titanium alloy parts having good heat resistance, comprising subjecting a titanium alloy composition consisting essentially of, by weight %, Al:

• 5.0-7.0%, Sn:
• 3.0-5.0%, Zr:
• 2.5-6.0%, Mo:
• 2.0-4.0%, Si:
• 0.05-0.80%, C:
• 0.001-0.200%, O:
• 0.05-0.20%, and the balance of Ti and inevitable impurities to the following sequential treatment steps:
• (1) a heat treatment step in β-region;
• (2) a rapid cooling step after the heat treatment in step (1) at a cooling rate higher than that of air-cooling to a temperature of 700° C. or lower;
• (3) a slow cooling step from a temperature of 700° C. or lower at a cooling rate of air cooling or lower;
• (4) a hot processing step in α+β region carried out at a temperature of β-transformation point or lower at a forging ratio of 3 or higher;
• (5) a solid solution treatment at a temperature of β-transformation point±30° C;
• and
• (6) an aging treatment at a temperature of 570-650° C.