Research On Forming Process Of Automobile Front Bracket

The sheet metal forming numerical simulation technology,which is used in the simulation of sheet metal stamping process,can not only be used to predict the forming defects of sheet metal,but also be used to optimize the process parameters,analyze the forming process,and evaluate the stamping die design.Therefore,the development cycle of stamping die can be shortened,the forming quality of the sheet metal parts improved,and the production cost reduced.In the field of sheet metal forming numerical simulation,a lot of research work has been done in the past,but there are few discussions about the process of forming optimization for a specific complex forming part.However,in practical engineering,for some parts with great difficulty in forming,it is often impossible to obtain the qualified parts only by stamping die tryout.The automobile front bracket,with complicated geometry,is difficult to stamping.In this paper,the forming process of the bracket part was developed,and the pretreatment setting for the numerical simulation of the drawing process of the part was analyzed and the meshing of tool body and sheet metal was emphatically analyzed.After the trial,the forming results and the rationality of the meshing were analyzed.The trial results show that there were fracture and wrinkle defects of the sheet metal at the same time,then,three sets of experiments based on single factor variation were carried out to investigate the influence of blank holder force,friction coefficient and punching speed on the forming results.The results show that both the blank holder force and the friction coefficient have a great influence on the forming results,and with the increase of the blank holder force and the friction coefficient,the number of fracture units increases,and the number of wrinkling units decreases,however,the forming speed has little influence on the forming results.After discovering the fracture and wrinkle defects of the sheet metal under various process parameters,the mold surface was modified reasonably combined with the deformation analysis of sheet metal fracture zone.And on this basis,furthermore,the process parameters of the blank holder force were optimized.The optimized process parameters and the shape of the die surface were used to make the actual test,and the qualified forming parts were obtained.At the same time,the results of the actual blank outline shrinkage are consistent with the results obtained by finite element method,and the rationality of the optimized process parameters and die surface was verified.