Hydrogen-induced porosity formed during solidification of aluminum-based alloys has been a major issue adversely affecting the performance of solidification products such as castings, welds or additively manufactured components. A three-dimensional cellular automaton model was developed to predict the formation and evolution of hydrogen porosity coupled with grain growth during solidification of a ternary Al-Si-Mg alloy. The simulation results fully describe the concurrent nucleation and evolution of both solidification grain structure and hydrogen porosity, yielding the morphology of multiple grains as well as the porosity size and distribution. This model was firstly validated in gravity die casting. Recently, this model has been extended to predict hydrogen porosity formation in aluminum laser welding and laser powder bed fusion additive manufacturing processes. These grain structure and porosity models have been validated by X-ray micro computed tomography (micro-CT), scanning electron microscopy (SEM) and optical metallography. With relatively large domains and high computational efficiency, CA models provide critical links between finite-element-based solidification process modeling and structural simulations of solidification products.

Moderated by: Daan Maijer / Michel Billet