Particulate Scale Numerical Investigation on the Compaction of TiC-316L Composite Powders

Abstract

This paper presents a numerical investigation on the 2D uniaxial die compaction of TiC-316L stainless steel (abbreviated by 316L) composite powders by the multiparticle finite element method (MPFEM). The effects of TiC-316L particle size ratios, TiC contents, and initial packing structures on the compaction process are systematically characterized and analyzed from macroscale and particulate scale. Numerical results show that different initial packing structures have significant impacts on the densification process of TiC-316L composite powders; a denser initial packing structure with the same composition can improve the compaction densification of TiC-316L composite powders. Smaller size ratio of 316L and TiC particles (R316L/RTiC = 1) will help achieve the green compact with higher relative density as the TiC content and compaction pressure are fixed. Meanwhile, increasing TiC content reduces the relative density of the green compact. In the dynamic compaction process, the void filling is mainly completed by particle rearrangement and plastic deformation of 316L particles. Furthermore, the contacted TiC particles will form the force chains impeding the densification process and cause the serious stress concentration within them. Increasing TiC content and R316L/RTiC can create larger stresses in the compact. The results provide valuable information for the formation of high-quality TiC-316L compacts in PM process.