MODELING AND SIMULATON OF PROCESS-STRUCTURE-PROPERTY OF MAGNESIUM ALLOY CASTING

The increasing needs from industry for efficient and economic manufacturing lead to the emergence and rapid development of integrated computational materials engineering (ICME) that integrates manufacturing simulation, advanced materials models and component performance analysis into a whole comprehensive framework, which can be used to optimize the manufacturing process, materials selection and product design. Modeling and simulation of process-structure-property is one of the primary themes of ICME. The present paper presents some latest research and development of modeling and simulation of magnesium (Mg) alloy castings at different length scales for predicting the microstructure and mechanical properties of the casting components, where macro-scale simulation of mold filling and solidification, microscale model of microstructure evolution during solidification, and mechanical property model based on structure information are demonstrated. The macro-scale simulation of the casting process took the process parameters as initial inputs and provided thermal history of the whole casting for micro-scale modeling. In the micro-scale modeling, the dendritic structure of primary phase was simulated in both two dimensions (2D) and three dimensions (3D) using a modified cellular automaton (MCA) model that takes heterogeneous nucleation, solute diffusion, interface curvature, and growth anisotropy into account. In the mechanical property modeling, main strengthening mechanisms of Mg-Al series cast Mg alloy were considered. Using the current model the yield strength distribution of Mg alloy wheel casting for automobile was predicted. Material property tests were carried out and the capability of the model was evaluated.