Stabilization of Injection by Optimizing Magnesium Plug in Hot Chamber Die Casting

Abstract

Our company produces die cast magnesium automobile parts by using a hot chamber plug-shot injection method. As the size of the plug generated at the end of the nozzle increases, injection variability increases, which affects product quality. Various experiments have been conducted on the working casting machine in efforts to mitigate this problem. In this study, the temperature distribution of the nozzle was analyzed and optimized by simulation. The length of the solidified plug was inferred from the temperature distribution of the nozzle and used in a smaller-is-better analysis, with the length as a characteristic value. This led to improved reproducibility and fewer defects, as confirmed on the working machine. The temperature gradient at the center of the nozzle was also analyzed, using the standard signal-to-noise ratio, and compared with the smaller-is-better analysis.