Research On Springback Of Arc Edge U Section Beam Forming And Car Side Door Sill Technology Development

In the middle and high grade car body is mainly by the high strength steel arc edge U section beam welding,arc edge U section beam forming and springback than straight edge U section beam is much more complicated.In addition,due to the high elastic modulus of high strength steel,the parts in forming,cutting edge,plastic and other process will appear a larger rebound deformation,seriously affect the overall quality of the frame welding.Because of the complexity of the form of springback,the mechanism of springback,the parameters of springback are more,the Springback Control is difficult to grasp,the arc edge U section beam needs to carry on the comprehensive and systematic research to the beam type parts with arc shape,and it provides the theoretical basis for the rationality of the process planning,the accuracy of the mold manufacture,and the superiority of the product quality.First,this study on high strength steel arc edge of the U-shaped section beam as the research object,based on the theory of metal plastic forming,according to the part geometry,forming characteristics,the were the division of different regions,analyzed the springback form of different regions,and on the basis of forming process of boundary conditions,yield criterion,work hardening assumption,based on the principal stress method,the theoretical analysis model of springback in each area of arc edge U section beam is established,and the calculation formulas of stress,strain,imaginary moment,different form of springback are deduced.Secondly,in deep drawing and elastic plastic mechanics theory as a guide,a certain curvature,wing wing width,drawing depth arc edge of the U-shaped section beam as the research object,according to the force balance method,it is concluded that the parts of the changes in the vertical section I SCO resistance.A finite element analysis model is established by using the finite element software ABAQUS,the verification,and to explore the parts in the forming law of the flow of materials in the process,the loading parts of the regional should unloading force and regional residual should force variation law.Again,for the influence of geometry and process parameters on springback,using finite element software DYNAFORM to established finite element analysis model,to explore the ridge curvature radius and width of the wing,friction coefficient,punch radius,die fillet radius of the prism arc U-shaped girder rebound effects of.At the same time,through physical experiments verify the parts of different curvatures and wing width on the forming law of the flow of materials and different wing fender width and the ridge curvature radius on the springback of the impact.Finally,using the above results,a vehicle side threshold after connecting plate as an example,develop a reasonable program,and carries on the springback analysis.Through the theoretical analysis and finite element simulation and physical experiment research of the arc edge U section beam,summed up the rebound,rebound computing formula and the process parameters influence each other,which provides theoretical guidance for the manufacture of automobile parts,it has certain practical application value.