The Research On Forming Simulation Of Automotive High-Strength Steel Blank And The Key Technology Of Stamping Parts' Unfolding

In the recent 20 years, the development of CAD/CAE/CAM technology has made a breakthrough on automobile panel's process and die design methods. With the development of numerical analysis technology, plastic processing technology, press technology, computer software and hardware technology and CAE technology, which is finite element centric technology, has made great progress. Numerical simulation technologies are applied to automobile panel forming process and die design optimization; it has great significance to improve the research capacity of automobile panel, especially in the quality, period, and cost of automobile panel, and fundamentally solve the problem of the long-term design of complicated die and difficulties to ensure the quality.The FEM sheet forming analysis system KMAS, which is produced by the Institute of Automobile Body and Die Engineering of Jilin University, plays a great role to the visual design and manufacture of automotive panels. Quickly perfecting the core function of KMAS system and enhancing its practical application to automotive production is the most important problem of the visual design software system we have been faced to deal with.Supported by the Key Project of the National Natural Science Foundation of China (No.19832020), the National Outstanding Youth Foundation (No. 10125208) and the Project 985-Automotive Engineering of Jilin University,"The Research on Forming Simulation of Automotive High-Strength Steel Blank and the key technology of stamping parts'mesh unfolding"is its core content.In this paper, a kind of arithmetic of surface identification and pick-up in the technology of punched-elements'unfolding based on mesh. It presents a new method to identify different kinds of surface including the link elements between the plat and bend mesh., and then using minimal multiplication to calculate the centre of a circle and its radius. It has also developed corresponding program and integrate it onto the whole KMAS system according to this research to improve some functions of this software system.By using KMAS system to analyze the forming process of High-strength steel blank, we take bracket equipment for changing BHF (blank holder force) to simulate. In order to simulate anomalistic forming problems, we use the method of interceptive lines'tangent approach. In addition, we use multi-stages forming process to increase the distortion capability of this kind of materials. Finally, we take a certain vent-pipe bracket to make this simulation and do our analysis, and testify the practicability and rationality of this optimization.