(1. 北京科技大学 新材料技术研究院 材料先进制备技术教育部重点实验室，北京 100083；
2. 辽宁忠旺集团有限公司，辽阳 111000)
摘 要: 采用挤压金属质点逆向追踪方法，分析了铝合金空心型材挤压过程中型材横断面温度分布不均匀性的原因及主要影响因素。结果表明：挤压过程中质点在分流孔内流动时的温度变化对模孔出口处型材横断面温度分布不均匀性的影响较大，而在焊合室内和模孔内流动时，温度变化对模孔出口处型材横断面温度分布不均匀性影响较小；挤压过程中各项热流作用对型材横断面温度分布不均匀性的影响程度由大到小依次为摩擦热、塑性变形热以及金属与工模具间的传热；通过模具结构设计和挤压工艺参数合理化，可使空心型材横断面温度分布的不均匀性得到较大的改善。
关键字: 铝合金；空心型材；分流模挤压；金属流动；横断面温度；不均匀性
（1. Key Laboratory for Advanced Materials Processing, Ministry of Education,
Institute of Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China;
2. Liaoning Zhongwang Group Co., Ltd., Liaoyang 111000, China）
Abstract:The reverse point tracking method was used to study the reason and influence factors of the temperature inhomogeneity on the cross section of Al alloy hollow profile. The results show that the temperature change in dividing process has a great effect on the temperature inhomogeneity on the cross section of the profile, while the effects of temperature change on the temperature inhomogeneity on the cross section of the profile in welding chamber and die hole are smaller. The influence extent of heat transfer during the extrusion on the temperature inhomogeneity on the cross section of the profile from large to small is friction heat deformation heat, and the heat transfer between the metal and die. By using the die structure design and the rationalization of extrusion parameters, the temperature inhomogeneity on the cross section of hollow profile is greatly improved.
Key words: Al alloy; hollow profile; porthole die extrusion; metal flow; cross section temperature; inhomogeneity
