|
The automobile rear corner window panels are typical automotive sheet metal stamping parts, not only deeides the quality of the automotive appearance, and slso requires the assembly accuracy,so need a high quality requirements. Due to the large-size of corner window structure, and the irregular surface formed by a number of free surface, more complex, found in the actual production process, if the process parameters and deformation mishandled, will the quality of the parts have a huge impact, parts reject rate rise, bringing great losses to the enterprise. Traditional methods for that such as seeking the optimum molding parameter of mould with existing experience before Repeating pre-stamping or mold trial can neither ensure the quality of the product nor shorten the cycle for research and development and impact of new product development.In order to solve the defect in forming process, based on existing theories and methods through the use of numerical simulation of sheet metal forming software DYNAFORM,to predicting the defects in the process, analyzes the reasons of the defects, with the experimental results of process adjustment, trying to solve the parts in the process of production, and the problems that appear to help enterprise shorten the development cycle, reduce scrap, improve efficiency.This paper summarizes the current status of China’s automobile industry, the evelopment process of the finite element method and numerical simulation of sheet metal forming domestic and overseas technology development and status, and a simple introduction for sheet metal forming simulation software DYNAFORM.Study describes the important theories of numerical simulation on sheet metal forming process of corner window panel, including:material yield criterion, elastoplastic FEM constitutive relationship, DYNAFORM software calculating module used mathematical algorithms:Display algorithms, and the need to use the simulation of complex mesh surfaces were discussed and elaborated plan for dealing with conflicts grid; Finally, a brief discussion of the friction problem of numerical computation.Summarizes the general steps of the numerical simulation of sheet metal forming, how to create a corner window in the plate finite element model, and the drawing forming process of the numerical simulation, by adjusting the draw bead on forming defects was improved, and completed The optimization of the process to get a better three-stage drawbead program.Summarizes the principles of LS-DYNA simulation of springback. Finishied the springback simulation analysis of corner window on the sheet metal forming and predict the maximum springback value 3.048435mm, correspond with production requirements, and Will not affect the quality of precision parts.
|