Finite Element Simulation And Experimental Research On Roll-Forming Process Of High Strength Steel

As a kind of economic sectional material, the cold-rolled forming section steel whichenjoys such merits as high-strength, light-weight and suitable sectional structure, is widelyused in the fields of building, household appliances, aviation, automotive industry and etc. Inrecent years, the cold-rolled forming section steel made from the high-strength steel isgaining more and more importance, especially in the automobile industry. This is attributedto the development of cold-rolled forming process. The application of the high-strengthcold-rolled forming section steel makes it possible to lighten the weight of the automobile,which is an encouraging prospect. Therefore, it is of a great significance to research theforming process of cold-rolled forming section steel.The research sets the door lining stiffener as the objective. With the aid of the finiteelement simulation software MSC.MARC, the numerical simulation model is established byanalyzing the characteristics in the cold-rolled forming process of the door lining stiffener. Inthe simulated research of the cold-rolled forming process of the door-lining stiffener, a seriesof results are found, such as the cloud chart as the equivalent stress and strain distribution indifferent forming stage, the history curves of equivalent stress and strain of one node in thecorner area. In addition, conclusions are made such as: The equivalent stress and strain aremainly distributed in the corner area and nearby while the maximum value is in the cornerarea; the maximum values of equivalent stress and strain increase with the forming step; Thevalue of the equivalent stress increases and decreases every time the node passing everyroller, which means that the roll forming is a process of repeated loading and unloading.By analyzing the cloud chart of the stress and strain distribution in the formingtransition zone, it is found that there is some plastic deformation of the high-strength steel inthe deformation transition zone. Through simulating and analyzing the influence of forming spring-back amount under different forming parameters in the process of the door liningstiffener, the result shows that: first, the spring-back increases with the decreased relativebending radius; second, the spring-back increases with the increased thickness of sheet;high-strength steel has much more spring-back than the common steel; the step space haslittle impacts on the spring-back.In this paper, it centered on the experimental research of the forming process of theautomobile door lining stiffener. On the basis of the simulate analysis, the forming process isestablished, the rollers are designed and the right forming units have been chosen to conductthe debugging of process equipment and process experiment. The problems arising from theexperiment are also researched and the solutions are found. The final excellent door rearinner stiffener plays a great role in the application and promotion of the high-strength steel inthe automotive industry.