Creep deformation and crack growth rates of a super α2 titanium aluminide alloy

The influences of stress and temperature on creep deformation behavior and the creep crack growth rates of the super α2 Ti3Al alloy were investigated with respect to its safe application at high temperatures. In a temperature range of 1033–1093 K at low applied stress levels, the stress exponent was equal to 1.5. At an intermediate stress range (10−3 < σ/E < 3 × 10−3), a stress exponent of 3.3 was observed. As the applied stress was increased, the stress exponent changed from 3.3 to 4.4. The high temperature crack growth rate of the Ti3Al alloy can be correlated with stress intensity factor K rather than C∗ at 1033 K due to environmental embrittlement.