Numerical process parameters optimization in hammer forging for minimizing forging load

抄録

Hammer forging is a traditional manufacturing technology to produce high stiffness product and is widely used in heavy industries. In the hammer forging, the product is produced through several blows. Forging using mechanical press controls the distance between dies and then the product is produced, whereas the product is produced by the energy in the hammer forging. Therefore, it is difficult to control the distance between dies in the hammer forging, and the energy plays a crucial role in the hammer forging. It is necessary to determine appropriate energy at each blow to produce highly accurate product. Conventionally, the energy at each blow is determined by the trial-and-error method. This paper proposes a methodology to determine the optimal energy at each blow using numerical simulation and design optimization technique. It is important to save the energy in the hammer forging for green environment, and is also important to reduce the forging load. To produce the highly accurate product, underfill should be avoided, which is handled as the design constraint. Therefore, multiobjective design optimization is performed to minimize the total energy and the forging load without underfill. The numerical simulation is so intensive that sequential approximate optimization that response surface is repeatedly constructed and optimized is adopted to identify the pareto-frontier between the total energy and the forging load. It is clarified through the numerical result that the proposed approach can determine the energy at each blow effectively, compared with the trial-and-error method.