中文摘要：

拉弯是型材的基本成形方法．截面畸变是型材拉弯成形中的常见缺陷，并对型材的回弹和变薄有交叉影响，型材拉弯成形性的分析评估远比板材成形复杂．提出了型材拉弯成形性的概念，建立了矩形截面型材拉弯成形性分析模型，基于有限元数值模拟研究了截面结构、相对高度和壁厚分布等几何参数对拉弯成形性的影响规律，从提高拉弯成形性出发提出了型材截面优化设计的原则．

英文摘要：

Stretch-wrap bending is the essential forming processing for profile. Cross section distortion is the common defect during the stretch-wrap bending of profile, and it brings cross-effect with thinning of thickhess and springback. The stretch-wrap bending formability for profile is much more difficult to analyze and to evaluate than that for sheet forming. The concept of stretch-wrap bending formability for profile was presented and an analytic model for profile with rectangular section was established. The effect of the geometric parameters such as section configuration, relative height and wall-thickness distribution of profile on stretch-wrap bending formability was studied based on finit element method （FEM） numerical simulation. The principle for optimization design of cross section was proposed in order to improve the stretch-wrap bending formability of profile.