Finite Element Modeling of the Hot Isostatic Pressuring Process

Abstract

In the hot isostatic pressing (HIP) process a container, with the approximate shape of the component to be produced, is filled with a metal powder, evacuated, and then subjected to high temperatures and pressures. As a result, the powder deforms to fill the void space and upon cooling a solid part results. Although the HIP process is cost competitive with forging, the costs for HIP could be reduced substantially if the final shape and size of the resulting component could be predicted. A computer aided modeling strategy for the HIP process has been developoed, and the results compare well with experimental measurements. This paper briefly discusses the macroscopic mechanical properties of powder metals, and the modifications of a finite element code required to include the powder mechanical properties. A more detailed discussion follows and includes: 1) the computer aided modeling strategy using a nonlinear finite element computer program, 2) the conclusions from a parametric study which indicated that the plastic deformations induced by the container were the primary source of the observed distortions, and 3) the results of a finite element model for an actual HIP which correlated well with experimental observations.