Abstract
At present, the qualified rate of large thin-walled magnesium alloy castings is low. In this study, the effects of mold structure and process parameters were investigated to improve the production qualification rate of castings. The filling process of die castings was simulated by numerical simulation technology to optimize their structure. On the basis of an optimized mold structure, the process parameters of die castings were optimized using a response surface model, and a group of optimal process combinations were obtained: pouring temperature—660 °C; mold preheating temperature—200 °C; injection speed—6.5 m/s. The rationality of the optimized mold structure and process parameters is verified by die-casting experiments. The results show that the optimized mold structure and process parameters can effectively reduce the internal shrinkage cavity casting defects of automotive CCB castings, and effectively improve the production qualification rate of magnesium alloy CCB castings. This research has important guiding significance for the production of large thin-walled magnesium alloy parts.