This paper discusses in detail the development of numerical simulations capable of simulating structural evolution and macroscopic deformation during a Powder Injection Molding process. A sintering model based on elastic-visco-plastic constitutive equations was proposed, and the corresponding parameters such as sintering stress, bulk and shearing viscosities were identified from dilatometer experimental data. As a complement to this experimental study, a finite element simulation of the sintering operation was performed. The simulations were based on constitutive equations identified from specific experiments performed for each blend at different sintering heating rates and loadings. Finally, the numerical analyses, performed on the 3D micro-structured components, allow the numerical predictions to be compared with experimental results of sintering stage. They show that the FE simulation results have better agreement with the experimental ones at high temperatures.