| Characterized by its inherent high strength, low spring back and good bump, the high strength steel was widely employed for auto-manufacturing sector in foreign countries. The use of high strength steel also became a major channel of realizing the automotive light weighting and improving the passive security. However, there was relatively little research on it mainly because of its poor forming capability in room temperature.Based on the numerical simulation and gray symtem theory, the paper conducts a research on the hot forming process of vehice's right bracket. The author analyses the influence of the process parameters on the result of forming, which include load mode of the blank holding force, draw bead, initial temperatures of the blank and mould, the stamping velocity etc by the elastic-viscoplastic FEM simulation. The findings the study can suggest as follows: The resistance of deformation and the flow stress will reduce while the forming quality obviously was improved with an increase of initial temperature of mould and blank; V shape curve of blank holding force is the best choice to forming; The possibility to appear crack will increase with decreasing of the round radius of the die and punch ;The inner stress will reduce while the stamping velocity increasing. When the temperature is 500℃,the author optimize the geometry parameters of draw bead and the hold binder force basing on the orthogonal experiments design.The best optimzation parameters are as follws: the hold binder force is 82KN,the draw bead height is 2mm,die round radius is 6mm.Contrasting the optimization results with the best simulation result in the orthogona experiments,the former has the more symmetrical thinkness, lesser winkle and crack trend ,The paper has met the expectations and the research findings have certain conductive significance to studying the forming of auto panel based on the numerical simulation and gray symtem theory...
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