Modeling, analysis, and multi-objective optimization of cold extrusion process of clutch outer gear hub using response surface method and meta-heuristic approaches

In this paper, a cold extrusion process was developed to manufacture the clutch outer gear hub. To reduce the forming load and improve the filling effect of internal spline fillet, this paper established the finite element (FE) model of the cold extrusion process and analyzed the influences of main process variables on the forming load and fillet clearance. Then, the second-order response models with four main process parameters as the optimization variables and forming load and fillet clearance as the optimization objectives were established by using the response surface method (RSM). Furthermore, the meta-heuristic approaches of non-dominated sorting genetic algorithm (NSGA-II) and multi-objective genetic algorithm (MOGA) were applied to optimize the models iteratively and a set of optimal process parameters was obtained. Finally, the finite element simulation and experiment confirmation results show that with the optimal parameters, the forming load can be effectively reduced and the filling effect of internal spline fillets is significantly improved. Thus, it is proved that the optimization method is feasible and that a clutch outer gear hub can be produced by cold extrusion process.