Finite element simulation of hot isostatic pressing of metal powders

Abstract

A finite element simulation of hot isostatic pressing of metal powders is studied using a mixed formulation method having velocity and pressure as nodal variables. A review of various methodologies formulated for the finite element modeling of hot isostatic pressing of powders is also presented. The constitutive relations considered are based on the theory of plasticity for powder material under the framework of hot deformations to model the creep behaviour of the powder material. The material behaviour of the container is modeled by incompressible plasticity via a power-law creep formulation. The extra constraints imposed in the axisymmetric approximation are eliminated by adapting suitable shape functions. The various material properties are assumed to be functions of temperature and relative density. The thermomechanical behaviour of powders is effectively modeled by a nonlinear transient heat transfer model, which is presented in the paper. A computational procedure for coupling the mechanical deformation with a thermal analysis is also addressed. The application of the present methodology is illustrated via the simulation of cylindrical powder metallurgy parts.