EXPERIMENTAL STUDIES AND NUMERICAL SIMULATION OF TWO-DIMENSIONAL ALUMINUM METAL FOAMING PROCESS UNDER EXTERNAL FIELD BEFORE SOLIDIFICATION

An improved lattice Boltzmann model is developed to simulate the aluminum foaming process produced with a blowing agent in which gas bubbles expand in the pseudo-plastic aluminum molten matrix. This paper discusses the investigations conducted to achieve an accurate two-dimensional (2D) model of the foaming process and simulation to describe precisely the formation of metallic foams and the expansion phenomenon. The present 2D metallic foam model authorizes enquiry of bubble germination and growth; the expansion process including foam pressure, foam velocity, and foam coalescence; and eventually the evolution of temperature. Finally, the model is validated with a few conditions such as high viscosity compared to a considered pure aluminum molten, gas diffusion, drainage phenomenon; and the numerical results are found to be consistent with the analytical results.