Mathematical modeling for high temperature flow behavior of as-cast Ti-45Al-8.5Nb-(W,B,Y) alloy

The hot deformation behaviors of as-cast Ti-45Al-8.5Nb-(W,B,Y) alloy were studied. A mathematical model has been developed to predict the stress-strain curves of this high Nb containing TiAl based alloy during hot deformation. This model is based on a phenomenological representation of the shape of stress-strain curves, which can be represented by Zener-Hollomon parameter in a hyperbolic sinusoidal type equation. Material constants in the equation were expressed in polynomial form of strain: parameters in the polynomials were obtained by least-square method. The stress-strain curves obtained by this model are in good agreement with experimental results. (C) 2008 Elsevier Ltd. All rights reserved.