压块对H96矩形管绕弯成形回弹与截面变形的作用  

Impact of pressure die on springback and section deformation of rotary-draw bending of rectangular H96 tube

作　　者：朱英霞[1] 刘郁丽[1] 杨合[1] 李海平[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室材料学院,西安710072

出　　处：《中国有色金属学报》2014年第1期104-114,共11页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(50975235);"111"引智计划资助项目(B08040)

摘　　要：为了控制矩形管绕弯成形的回弹和截面变形,建立考虑压块力、速度加载条件的回弹和截面变形有限元预测模型,并对其可靠性进行实验验证。基于所建模型研究压块的摩擦因数、夹持压力和助推速度对H96矩形管回弹与截面变形的影响规律。结果表明:摩擦因数和夹持压力越大,回弹角和横截面高度变形越小。但压块对横、纵截面畸变的作用完全相反;芯头支撑区域内助推速度的变化能够影响回弹量,且不会加剧截面变形。提出变助推速度的压块边界条件组合方案,实现了弯曲角度小于90°和大于等于90°弯管的回弹量分别降低55.31%和36.45%,60°弯管的高度变形量平均降低1.79%,90°和120°弯管的高度变形量最大分别降低5.98%和6.35%。In order to control springback and section deformation of rotary-draw bending of rectangular tube, the finite element model for springback and sectional deformation prediction, which considers the loading and velocity conditions of pressure die, was established and verified by experiment. Based on the model, the impact of friction coefficient, pressure and boosting velocity of pressure die on springback and section deformation of H96 rectangular tube was investigated. The results show that the larger the friction coefficient and the clamping pressure are, the smaller the springback angle and the cross-section height deformation are. However, the impacts of pressure die on deformations of cross-section and longitudinal-section are completely opposite. The change of boosting velocity within core-filled area can influence the springback amount, while not exacerbate section deformation at the same time. Then, the combinations of pressure die boundary conditions of variable boosting speed were proposed. And by which, it is realized that springback angles are decreased by 55.31%and 36.45%, respectively, for bent tubes smaller than 90° or no less than 90°. The cross-section height deformations are reduced by 1.79%for 60° tube on average, and 5.98%and 6.35%, respectively, for 90° tube and 120° tube at most.

关 键 词：绕弯成形 H96矩形管 回弹 截面变形 工艺参数 有限元模拟 

分 类 号：TG386[金属学及工艺—金属压力加工]