中文摘要：

基于Dynaform软件平台，建立了Y型异径三通管三维弹塑性有限元模型。运用数值模拟方法，研究了AZ31镁合金Y型异径三通管热态内高压成形过程。探讨了摩擦系数对成形结果的影响，以内压力、左右冲头进给量、中间冲头后退量为因子，设计了正交试验方案，获得了优化的加栽路径。结果表明：摩擦系数越小，三通管成形质量越好；通过正交试验优化方案能够成形综合质量较高的Y型异径三通管。

英文摘要：

Based on Dynaform software environment, a 3D elastic--plastic finite elemem model for Y--shape reducing tee was estahU, shed. With numerical simulation, the warm hydroforming process of AZ31magnesium alloy Y--shaped reducing tee were studied. The effects of friction coefficient on the protrusion height and wall thickness were investigated by numerical sim- ulation. Orthogonal experiment was carried out, inner pressure left and right axial feed and the feed of the middle punch set as variances, the optimization of the loading path were obtained. The results show the shorter is friction coefficient, the greater is the protrusion height formed, the forming quality of Y-shaped tube can be improved in this method.