Phase-field simulation of Mo powder during sintering process

The formation, growth of the sintering necks and the spheroidization of the pores, which are mainly controlled by surface diffusion and grain boundary diffusion during the sintering of Mo powder, were simulated respectively by using both four-ball and five-ball model. In the simulation process, the relative density fields governed by Cahn-Hillard equation and the long-range-order (LRO) parameter fields controlled by Ginzburg-Landau equation (TDGL)were introduced, and a semi-implicit Fourier-spectral method was used to solve the above-mentioned equations. The simulation results show that the dominant diffusion mechanism in the sintering process of Mo powder is surface diffusion, and the higher the density of green compact, the shorter the sintering time.