Establishment of the Constitutive Relationship for MP159 Alloy

The constitutive relationship for MP159 alloy, a kind of high strength cobalt-base superalloy, was studied based on the experimental results of compression tests carried out in the THERMECMASTER--Z hot work simulating test machine. The constitutive relationship model using Zener-Hollomon parameter as primary variable is proposed, and the constitutive equation for MP159 alloy is firstly formulized. This equation well represents the relationship of flow stress with thermomechanical parameters, i.e. strain, strain rate and temperature, in a large deformation (a true strain of 1.10) and a wide range of deformation temperatures and strain rates. It can be used for the finite element simulation of plastic forming process and the dissipative structure theory and dynamic material modeling.