中文摘要：

利用有限元模拟软件ABAQUS建立了0Cr21Ni6Mn9N不锈钢管材的数据弯曲、抽芯及回弹全过程有限元模型，并对其可靠性进行了验证；研究了芯棒伸出量e对横截面畸变、壁厚变化、起皱趋势和回弹角的影响规律。结果表明，随着芯棒伸出量的增大，管材横截面畸变率和回弹角减小，当芯棒伸出量大于2．5mm时，管材出现“鹅头”现象；外侧壁厚减薄率随着芯棒伸出量的增大而增大，内侧壁厚增厚率随着芯棒伸出量的增大而有所减小，但减小趋势不明显；弯管内侧起皱趋势随着芯棒伸出量的增大先减小后增大；最后获得了合适的芯棒伸出量范围为1．5～2mm。

英文摘要：

A finite element model for the NC bending, retracting and springback process of 0Cr21Ni6Mn9N stainless steel tube was estab- lished with FE software ABAQUS and its reliability was verified. Based on the model, the influences of mandrel extension length e on the cross section deformation, change ratio of wall thickness, wrinkling tendency and springback angle were analyzed. The results show that the cross section deformation ratio and springback angle decrease as mandrel extension length e increases, when e is greater than 2.5 mm, tube appears ＂goose head＂ phenomenon. With the increase of mandrel extension length, the outside wall thinning ratio increases, inside wall thickening ratio decreases, and the decreasing tendency is not obvious. With the increase of mandrel extension length, the wrinkling tendency decreases firstly and then increases. The suitable mandrel extension length range is 1.5 - 2 mm.