Li Yong, He Chen, Li Jiadong, Wang Zhaodong, Wu Di, Xu Guangming
State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819, China.
Key Laboratory of Electromagnetic Processing of Materials, Ministry of Education, Northeastern University, Shenyang 110819, China.
Materials (Basel). 2020 Apr 6;13(7):1713. doi: 10.3390/ma13071713.
The main purpose of this present study was to investigate the different processing conditions on the microstructure, segregation behavior of alloying elements, and mechanical properties of Al-Mg-Si alloy twin-roll cast slab prepared using a novel twin-roll casting technology. The simulation of temperature field, distribution of alloying elements, tensile properties, hardness, and conductivity were examined by a Leica optical microscope, scanning electron microscopy, energy dispersion spectroscopy, electron probe microanalysis, and tensile tests. The results indicated that when the traditional twin-roll casting method was used to produce aluminum alloy strip, there are obvious centerline segregation defects due to the deep crystallization front depth and symmetrical solidification characteristics. When the forced-cooling technology was applied in the twin-roll casting process, by virtue of the changing of crystallization front depth and crystallization front shape, the segregation defects are obviously suppressed. Suggesting that this method can significantly improve the uniformity of alloying elements in the thickness direction of the twin-roll cast slab, ultimately improve the mechanical properties of AA6022 aluminum alloy.
本研究的主要目的是研究采用新型双辊铸轧技术制备的Al-Mg-Si合金双辊铸坯在不同加工条件下的微观结构、合金元素的偏析行为及力学性能。通过徕卡光学显微镜、扫描电子显微镜、能谱仪、电子探针微分析和拉伸试验对温度场模拟、合金元素分布、拉伸性能、硬度和电导率进行了检测。结果表明，采用传统双辊铸轧法生产铝合金带材时，由于结晶前沿深度较深和凝固特性对称，存在明显的中心线偏析缺陷。在双辊铸轧过程中应用强制冷却技术时，由于结晶前沿深度和结晶前沿形状的改变，偏析缺陷得到明显抑制。这表明该方法可显著提高双辊铸坯厚度方向上合金元素的均匀性，最终改善AA6022铝合金的力学性能。
