DP800双相高强钢折弯及回弹研究

Bending and Springback of High-strength Dual Phase Steel DP800

目的针对高强度钢板成形过程中的回弹问题,研究工艺参数对回弹的影响规律,优选工艺参数组合,以获得回弹较小的V形件。方法采用dynaform软件对V形件进行成形及回弹的数值模拟,以摩擦因数、模具间隙、冲压速度、凹模圆角半径等工艺参数为自变量,以回弹前后水平距离差最大值为因变量,设计了四因素三水平的正交试验方案,研究多个工艺参数对回弹影响的规律。结果实验结果表明,V形件回弹值大小随着摩擦因数的增大呈现减小趋势;随着模具间隙、凹模圆角半径的增大,回弹值呈现增大的趋势;而冲压速度对V形件回弹的影响较小,且工艺参数影响V形件回弹大小的主次顺序为模具间隙、摩擦因数、凹模圆角半径、冲压速度。结论优选工艺参数组合为:摩擦因数为0.2、模具间隙为2.6 mm、冲压速度为1200 mm/s、凹模圆角半径为12 mm,此时回弹水平距离差最大值为0.566 mm,最大减薄率为1.40%;实际生产可以忽略冲压速度对回弹的影响,仿真结果对实际生产具有指导意义。

As for the springback of high-strength steel forming process, in order to study the influence rule of process parameters on springback, optimize the combinations of process parameters and obtain a smaller V-shaped springback value, dynaform software was used to carry out numerical simulation for the forming and spring back of V-shaped workpiece. An orthogonal experimental plan of four factors and three levels was worked out with process parameters, i.e. friction coefficient, die clearance, punch speed and radius of bottom die as independent variables and the maximum horizontal distance difference before and after springback as the dependent variable, so as to research the influence rule of several process parameters on the springback. The experiment showed that the springback of V-shaped workpiece gradually reduced along with the increase of the friction coefficient and got bigger along with the increase of die clearance and radius of bottom die; The punch speed had little influence on the springback of V-shaped workpiece and the process parameters influenced the V-shaped springback in the order: first die clearance, friction coefficient, radius of bottom die, and last punch speed. The optimal process parameters are: friction coefficient 0.2, die clearance 2.6 mm, punch speed 1,200 mm/s, radius of bottom die 12 mm. With these optimal parameters, the maximum springback horizontal distance difference is 0.566 mm and the maximum reduction rate is 1.40%; the impact of punch speed on the springback can be ignored in actual production, and the simulation results have practical significance for the production.