PHASE-TRANSFORMATIONS IN TI-40AL-10V

Phase transformations in arc melted Ti-40Al-10V ingots have been studied. Solidification started with the bcc beta phase. The room temperature microstructure consisted of B2,omega(ord) (ordered omega), gamma and alpha(2) phases. The alpha(2) phase was generally found in bands of (alpha(2) + gamma) and was richer in V and Ti than the gamma phase. Orientation and interfacial relationships have been determined. The fine structures of the gamma phase and different morphologies of the (alpha(2) + gamma) structure have been studied by electron microscopy. It is shown that the phase transformation sequence in the alloy is L --> L + beta --> beta --> alpha + beta --> alpha + B2 --> alpha(2) + gamma + B2 --> alpha(2) + gamma + B2 + omega(ord).