中文摘要：

针对金属体积成形过程中有限元网格畸变和再划分问题,研究了工件网格畸变单元中表面四边形面片分解为三角形面片时的重叠问题,提出了将工件与模具接触区域的工件三角形面片用模具表面三角形面片代替的算法,并给出了接触区域判断、相交点计算、相交三角形环的二次剖分以及融合拼接等关键技术,算法能够很好地描述工件与模具接触区域的形状特征,可显著降低模具干涉对网格再划分的影响,获得质量优良的再划分网格。

英文摘要：

Aiming at the problem of finite element mesh distortion and mesh regeneration in metal forming process,this paper studies the degeneracy problem of the distorted elements in the process of dividing a quadrilateral free face into two triangles.To reduce the impact of geometrical interference between workpiece and die,the workpiece＇s triangle facets in the contact region are substituted by the die＇s triangle facets.The key techniques in the method are presented in detail,such as the contact region judgement,the intersection point calculation,the intersected triangle subdivision,the integration and connection,etc.This algorithm can give good description of the shape features in the contact region of the die and workpiece,reduce the impact of the die interference to the mesh regeneration and obtain excellent resulting meshes.