Simulation of hot isostatic pressing of metal powder components to near net shape

摘要

Presents a finite element formulation of hot isostatic pressing (HIP) based on a continuum approach using thermal-elastoviscoplastic constitutive equations with compressibility. The formulation takes into consideration dependence of the viscoplastic part on the porosity. Also takes into account the thermo-mechanical response, including nonlinear effects in both the thermal and mechanical analyses. Implements the material model in an implicit finite elemeat code. Presents experimental procedures for evaluating the inelastic behaviour of metal powders during densification and experimental data. Chooses the simulation of the dilatometer measurement of a cylindrical component during HIP and manufacturing simulation of a turbine component to near net shape (NNS) as a demonstrator example. Both components are made of a hot isostatically pressed hot-working martensitic steel. Compares the result of the simulation in the form of the final geometry of the container with the geometry of a real component produced by HIP. Makes a comparison between the calculated and measured deformations during the HIP process for the cylindrical component. Measures the final geometry of the turbine component by means of a computer controlled measuring machine (CMM). Performs the complete process from design and simulation to geometry verification within a computer-aided concurrent engineering (CACE) system.