Al-Mg-Si-Cu合金挤压型材中晶粒异常长大行为研究-中国材料进展

文章信息/Info

Title:: Study on the Abnormal Grain Growth Behavior in Al-Mg-Si-Cu Alloy Extrusion Profile

作者:: 庞新义; 汪文进; 杜东海; 1. 西北工业大学太仓长三角研究院清洁能源研究院，江苏太仓 215400 2. 明达铝业科技（太仓）有限公司，江苏太仓 215400

Author(s):: PANG Xin-yi; WANG Wen-Jin; DU Dong-hai; 1. Clean Energy Research Center, Yangtze River Delta Research Institute,Northwestern Polytechnical University,Taicang 215400, China 2. Minta Aluminum Co., Ltd., Taicang 215400, China

Keywords:: Al-Mg-Si-Cu alloy; extrusion process; abnormal grain growth; solid solution strengthening; tensile property

摘要:: 挤压型材晶粒的异常长大是限制铝合金力学性能提高的重要原因之一，揭示挤压型材晶粒异常长大的机理及对其力学性能的影响，对调控挤压参数、提高合金力学性能有重要意义。通过研究挤压温度、挤压速度对Al-Mg-Si-Cu合金组织和性能的影响发现，晶粒的异常长大与合金表层晶粒较大的剪切变形以及心部<100>//ED优先生长晶粒与周围变形晶粒之间较大的取向差和应变梯度促进了合金再结晶过程有关。因固溶强化效应，合金拉伸性能随挤压温度、挤压速度的升高而提升。挤压型材出口温度高于550 ℃时，合金的拉伸性能更加优异。

Abstract:: The abnormal growth of grain in extruded aluminum profiles is one significant factor that affects the improvement of the mechanical properties of the alloy.Understanding the mechanism behind the abnormal growth of grain in extruded aluminum profiles and its effect on mechanical properties is crucial for controlling extrusion parameters and enhancing the properties of the aluminum alloy. In this paper, the effects of extrusion temperature and extrusion rate on the microstructure and properties of Al-Mg-Si-Cu alloys were investigated. The results show that the abnormal grain growth is due to the large shear deformation of the surface grain layer during the extrusion process and strain gradient and misorientation between the <100>//ED preferentially growing grains in core and the surrounding deformed grains, which promotes the recrystallization process of the alloy. According to the solid solution strengthening effect, the tensile properties of alloy are improved with the increase in the extrusion temperature and speed. Moreover, the tensile properties of the alloy are exceptionally good when the outlet temperature of the extruded profile exceeds 550 ℃.