Research On Springback Algorithm And Distribution Law Of Variable Curvature Concave Cueve Flanging Parts

The rubber forming is one of the important processes in aviation sheet metal manufacturing.In order to improve the forming quality and efficiency of sheet metal parts,in this paper,a theoretical model of variable curvature concave curve flanging part was established,and the springback distribution law of variable curvature concave curve flanging part was studied.Combined with the finite element simulation technology,the factors influencing the springback of the flanging part with variable curvature concave curve were explored.The springback compensation is carried out on the working surface of the forming die.It can solve the springback of the flanging part with variable curvature concave curve,and improves the part forming quality.The theoretical springback algorithm of variable curvature concave curve flanging parts was obtained.Taking 2024 aluminum alloy with 1 mm thickness as the research object,uniaxial tensile tests were carried out on materials in different rolling directions under the new quenching state.The mechanical properties parameters of the materials were obtained,which lay a foundation for subsequent finite element simulation and springback compensation calculation.The influence of curvature radius and flanging curve length on springback was analyzed by finite element simulation software.The results show that:the flanging position of variable curvature concave curve flanging parts mainly bears tensile stress,which results in sheet metal thinning from the central position to both ends obviously,the springback value increases slowly in a quadratic function from the central position to both ends.At the central position,the springback value is the smallest,with the decrease of curvature radius,the springback value increases continuously and reaches the peak at the free end.Under the same conditions,the greater the curvature is,the larger the springback value is.When the curvature changes uniformly,the shorter the length of the variable curvature curve is,the more likely it is to warp at the free end,and the greater the springback value is.Through CATIA secondary development system,the normal plane springback compensation was carried out for typical spacer frame parts.The finite element simulation and forming test were carried out for the compensated die.The angles of the parts’ curve flanging after forming were measured and the results meet the design standards,through which effectiveness of theoretical springback algorithm and surface springback compensation is verified,and the springback of variable curvature concave curve flanging parts is solved.