锻压技术

中空铝合金型材拉弯成形工艺研究

英文标题：Research on stretch bending of hollow aluminum alloy profile

作者：刘学之张石磊李世涛刘纯国张学广

分类号：TG302

出版年,卷(期):页码：2015,40(5):69-73

摘要：

拉弯成形工艺具有成形精度高、回弹量小、生产效率高的优点，对轨道列车端顶弯梁进行拉弯数值模拟与成形实验。利用数学解析法计算得到了型材拉弯过程中夹钳的运动轨迹，并定义了型材拉弯过程中典型的成形缺陷。利用有限元模拟对比分析不同选材和工艺参数下成形后零件的应力分布、回弹、截面畸变和空间扭转。研究结果表明：选用ENAW-6005-T4材料可以避免型材拉弯过程中的断裂；采用预拉0.5%和补拉1.5%的加载组合时，型材的卸载回弹量最小；采用1.5 MPa的填充压强可以有效地抑制型材外壁的内凹；改善摩擦条件可以减小成形后的空间扭曲。采用优化后的工艺参数进行了实验验证，测量结果和数值分析规律相吻合。

The advantages of stretch bending are excellent forming accuracy, low springback and high production efficiency. Numerical simulation and forming experiment on the end bending beam of rail train were carried out. The trajectory of jaw was obtained by mathematical analysis, and the typical forming defects were defined in stretch bending process of aluminum alloy profile. The stress distribution, springback, cross-section distortion and spatial twist of formed parts were compared and analyzed for different materials and processing parameters by numerical simulation. Numerical simulation results show that ENAW-6005-T4 material can avoid fracture in stretch bending. The loading couple of 0.5% pre-stretch and 1.5% post-stretch can minimize the springback. The filling pressure of 1.5 MPa can restrain the concave of side wall effectively. The spatial twist can be decreased by improving the frictional condition. Experimental validation was conducted with the optimized processing parameters, and measured results show a consistency with numerical analysis.

基金项目：

国家自然科学基金资助项目（51275203）

刘学之（1962-），男，硕士，高级工程师

参考文献：

［1］王汝彪, 刘纯国. 高强度中空铝型材成形工艺研究 [J]. 锻压装备与制造技术, 2013, 3(2):93-96.Wang R B, Liu C G. The research on forming process of high strength hollow aluminium alloy [J]. Equipment & Manufacturing Technology, 2013, 3(2): 93-96.
［2］Vollersten F, Spenger A, Kraus J, et al. Extrusion, channel, and profile bending: A review [J]. Journal of Materials Processing Technology, 1999, 87(1-3): 1-27.
［3］Clausen A H, Hopperstad O S, Langsten M. Stretch bending of aluminium extrusions for car bumpers [J]. Journal of Materials Processing Technology, 2000, 102(1-3): 241-248.
［4］李小强, 周贤宾, 金朝海, 等. 型材拉弯数值模拟夹钳边界条件的一种等效模型 [J]. 塑性工程学报, 2009, 16(1): 64-69.Li X Q, Zhou X B, Jin C H, et al. An equivalent model of jaws boundary condition in numerical simulation of stretch bending for extrusions[J]. Journal of Plasticity Engineering, 2009,16 (1):64-69.
［5］刘天骄, 王永军, 夏晓娇, 等. 型材拉弯数值模拟轨迹建模方法 [J]. 锻压技术, 2014, 39(7)：132-137.Liu T J, Wang Y J, Xia X J, et al. Trajectory modeling of extrusion stretching bending simulation [J]. Forging & Stamping Technology, 2014, 39(7): 132-137.
［6］尹丽丽. 6005A合金的加工特性和性能 [J]. 轻合金加工技术, 2000, 28(6): 41-43.Yin L L. Properties and processing characteristic of 6005A alloy [J]. Light Alloy Fabrication Technology, 2000, 28(6): 41-43.
［7］万敏, 洪振军, 李卫东, 等. 大型异型材拉弯成形有限元模拟技术研究 [J]. 锻压技术, 2008, 33(5): 160-164.Wan M, Hong Z J, Li W D, et al. FEM simulation technology on stretch bending of long profile with complex section [J]. Forging & Stamping Technology, 2008, 33(5): 160-164.
［8］Yu C H, Li X Q. Theoretical analysis on springback of L-section extrusion in rotary stretch bending process [J]. Transactions of Nonferrous Metals Society of China, 2011, 21(12): 2705-2710.
［9］詹梅, 项增新, 杨合, 等. 复杂截面型材拉弯截面畸变研究[A]. 第十届全国塑性工程学术年会、第三届国际塑性加工先进技术研讨会[C].南昌, 2007.Zhan M, Xiang Z X, Yang H, et al. Cross-section distorition during stretch bending of profile with complex section[A]. The 10th National Symposium of Plasticity Engineering & The 3rd International Symposium on Advanced Plastic Processing Technology[C].Nanchang, 2007.
［10］Corona E. A simple analysis for bend-stretch forming of aluminum extrusions [J]. International Journal of Mechanical Sciences, 2004, 46(3): 1130-1135.
［11］Clausen A H, Hopperstad O S, Langsten M. Sensitivity of model parameters in stretch bending of aluminium extrusions [J]. International Journal of Mechanical Sciences, 2001, 43(2): 427-453.

服务与反馈：

【本网站尚未开通全文下载服务】【加入收藏】