冷間鍛造における割れ危険性と成形エネルギの抑制を目的としたプロセスパラメータの最適設計

抄録

Cold forging is a typical manufacturing technology to produce various mechanical components with high productivity. Various process parameters such as punch velocity and forging loads are adjusted for successful forging. In this paper, a backward extrusion of aluminum alloy using the spring devices is considered. The target product handled in this paper has earing, around which the risk of crack is high with inappropriate process parameters. Therefore, it is important to determine optimal process parameters to minimize the risk of crack. In addition, in the cold forging, it is important to form the product with minimum forging load. In this paper, a multi-objective process parameters optimization minimizing the risk of crack and the forging energy is performed using numerical simulation. Numerical simulation in the forging is so intensive that sequential approximate optimization using radial basis function is adopted to determine the optimal process parameters with a small number of simulations. Through the numerical result, the pareto-frontier between the risk of crack and the forging energy is clarified. In addition, it is found that the smooth flow lines along the product shape can be obtained. Based on the numerical result, the experiment is also carried out to validate the proposed approach.