Formation of α-Widmanstatten structure:: effects of grain size and cooling rate on the Widmanstatten morphologies and on the mechanical properties in Ti6Al4V alloy

The coarseness of the transformed beta -heat treated Ti6A14V has a strong influence on its properties. The effects of solution temperatures and cooling rate on the Widmanstatten morphologies and on mechanical properties have been determined. The alpha -Widmanstatten plates size increases when the cooling rate decreases and a certain decrease of alpha -allotromorphous phase size at the grain boundaries can be observed when the cooling rate is increased. The tensile strength can be reduced about 80 MPa with the slower cooling rate from the beta annealing temperatures when comparing air cooling to water quenching for thinner section sizes. (C) 2001 Elsevier Science B.V. All rights reserved.