(1. 北京科技大学 新材料技术研究院，北京 100083；
2. 内蒙古工业大学 材料科学与工程学院，呼和浩特 010051)
摘 要: 采用Deform-3D有限元软件，结合基于逆向工程的焊合面网格修复技术，建立方形管分流模双孔挤压时包括焊合过程在内的全过程的三维有限元数值模拟方法，分析分流孔的配置方案对金属流动行为、挤压力、挤压温度及成形质量的影响。结果表明：中间分流孔与位于两侧分流孔的面积比值Q1/Q2是影响金属流动均匀性、焊缝位置和制品平直度的重要因素，比值Q1/Q2为0.93~1.03时，挤出的方管平直度好；分流孔外接圆直径和挤压筒直径的比值对挤压过程中温升的影响较小，而对挤压力有一定的影响，当该比值为0.82时挤压力最小，该比值超过0.82时挤压力明显增加。
关键字: 分流模挤压；有限元模拟；分流孔面积；金属流动行为
square tube with porthole die
（1. Institute of Advanced Materials and Technologies, University of Science and Technology Beijing, Beijing 100083, China;
2. School of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot 010051, China）
Abstract:Applying welding plane meshes repairing technology based on reverse engineering and commercial FEM soft Deform-3D, a three dimensions finite element method for simulating the whole diplopore extrusion process of square tube with porthole die, including bonding stage, were developed. The effects of the portholes configuration scheme on the metal flowing behaviors, extrusion load, tube temperature and forming quality were analyzed. The results show that, the area ratio of the center to the side porthole (Q1/Q2) is an important factor affecting the flow uniformity, seam position and straightness of the tube. When the area ratio (Q1/Q2) ranges in 0.93−1.03, the straightness of the extrusion tube is satisfied. The diameter ratio of the porthole circumcircle to the extrusion container (Dc/D) has little effect on the temperature-rising, but has great effect on the extrusion load. When the diameter ratio is 0.82, the extrusion load is at minimum. When the diameter ratio is larger than 0.82, the extrusion load increases obviously.
Key words: porthole die extrusion; finite element simulation; porthole area; metal flowing behavior
