Modelling and Numerical Simulation of Thermal Debinding Processing in Powder Injection Moulded Parts

摘要

Powder injection molding (PIM) is an important net-shape manufacturing process. Thermal debinding is a common methodology for the final removal of residual polymer from green parts prior to sintering step. This process is a complex combination of polymer pyrolysis and heat transfer in porous medium. In this paper, numerical simulations of the thermal debinding process based on a coupled mathematical model for mass diffusion and heat transfer in deformable porous medium are proposed. The present numerical simulations are carried out to describe the thermal debinding process of PIM parts. The established model takes into account of the thermal degradation and polymer diffusion inside the PIM components. The basic equations of this model consist to solve the following coupled problems: thermal degradation and polymer diffusion, heat transfer and deformation phenomena using finite element method with Comsol software. Based on the numerical results, remaining binder distribution, temperature distribution and deformation during thermal debinding processing are predicted.