Mechanical properties and microstructure of an α plus β titanium alloy with high strength and fracture toughness

The Ti-Al-Sn-Zr-Cr-Mo-V-Si (Ti-62A) alloy, an alpha-beta alloy with high strength and fracture toughness, is currently used as an advanced structural material in aerospace and non-aerospace applications. Thermo-mechanical processes can be used to optimize the relationship between its strength and fracture toughness. A Ti-62A alloy bar can be machined through a transus beta-forged plus alpha+beta solution treated and aged specimen with a lamellar alpha microstructure. The effects of heat treatment on the mechanical properties were discussed. Heat treatment provided a practical balance of strength, fracture toughness, and fatigue crack growth resistance. A comparison of the Ti-62A alloy with the Ti-62222S alloy under the same thermo-mechanical processing conditions showed that their properties are at the same level.