The Finite Element Simulation And Optimization Of Sub-frame Hydroforming Process

The most important means of transportation in our daily life is car, both in number and frequency of using is a big number, even a tiny progress of the automobile industry, will be a great progress for the whole world. the most direct and effective way is to "lightweight". When the weight of the body is reduced, under the condition of same power capacity will rise, so the fuel efficiency will improve. While under the same load lighter body representing the lower fuel consumption and fewer emissions, so the car's "lightweight" get a high degree of attention, someone will question whether reduce body weight means less security, the answer is no, two conflicting issues under the new technology has obtained the unified solution, this is what the rest of this article is to mention the internal high-pressure forming technology.In this paper, simulation software: Autoform was used to research the whole forming process of vice frame, Including: bending, preforming and internal high pressure forming three main processes and discussed what problems will happen in each steps. And according to the corresponding evaluation criteria, in bending process, the bending radius, bending steps have been adjusted to adapt to the actual processing. In preforming process, the forming die is designed by the cross-section shape. The important parameters of inner high pressure forming such as feeding, forming pressure, plastic pressure, initial pressure and load were simulated respectively. By analyzing the wall thickness distribution under different parameters and forming limit FLD diagram, we can obtain the optimal forming results.In the final chapter of this paper, the correctness of the simulation results can be verified by experiment, The forming effect was conformed with relevant international standards, then test the wall thickness and compare with the simulation values, the result shows that The difference of the wall thickness was in a reasonable range, it can be concluded that the simulation results are in conformity with the actual processing.