Parameter optimization in hot precision forging process of synchronizer ring based on grey relational analysis and response surface method

Abstract

In this work, the hot precision forging process was proposed to manufacture the synchronizer ring made of HMn64–8–5–1.5 alloy, and the forming process parameters were optimized. The true stress-strain data of HMn64–8–5–1.5 alloy were obtained through the isothermal compression test. Then, the finite element model of the hot precision forging process of the synchronizer ring was built, and two schemes of the forming process were analyzed and compared. To solve the problems during the hot precision forging process of synchronizer ring, i.e. forging defects, low material utilization and large forming load, a multi-objective optimization method based on grey relational analysis (GRA) and response surface method (RSM) were introduced to optimize the process parameters. As a result, a set of optimal process parameters was determined through the model calculating. Numerical simulation and experiment were carried out to verify the optimal scheme, which was set up based on the obtained optimal process parameters. The results of experimental and numerical simulation have good consistency. The results show that the optimal scheme can ensure product quality, enhance material utilization and reduce forming load.

Keywords

• Synchronizer ring
• hot precision forging
• grey relational analysis
• response surface method
• parameter optimization