L型截面铝型材拉弯成形截面畸变缺陷控制研究

以某轨道车辆L型截面铝型材构件为研究对象,利用数值模拟技术分析了L型截面铝型材拉弯成形中常见截面畸变缺陷的成因,研究了模具结构参数对截面变形的影响规律,提出相应截面畸变缺陷的控制措施,并通过试验进行了验证。结果表明:L型截面铝型材拉弯成形主要截面畸变缺陷为立边倾斜和横边塌陷;立边倾斜缺陷主要因挡板间隙不合理引起,优化挡板间隙能够有效控制立边倾斜缺陷;横边塌陷主要因拉弯过程中立边收缩引起,基于相应位置的立边收缩量,通过减小拉弯模具支撑面的深度能够有效控制横边塌陷缺陷。

Section distortion control for L-section aluminum profile part in the stretch-bending process

For L-section aluminum profile part in a rail vehicle, the causes producing the section distortion defects in stretch-bending process were analyzed by the numerical simulation, and the influences of the bending die structure parameters on the section deformation were studied. Then, the corresponding defect controlling methods were proposed and verified by tests. Results show that the general sec-tion distortion defects are the vertical wall obliquing and the horizontal plate collapsing. The former is caused by the unreasonable holder gap, which can be controlled by optimizing the holder gap, while the later is mainly induced by the shrinkage of the vertical wall, which can be controlled by decreasing the depth of the die supporting surface based on the shrinkage degree of the vertical wall.