固体冷料占比对双零铝箔用铸轧板组织性能的影响

为了优化电解铝液中固体冷料占比，稳定获得高品质铝合金熔体，以8079铝合金为研究对象，利用ABB测氢仪检测了铸轧生产时不同固体冷料占比(0%、20%、30%、40%、60%、70%)铝合金熔体含氢量，借助光学显微镜(OM)、扫描电子显微镜(SEM)和能谱分析仪(EDS)等分析方法对双零铝箔用铸轧板微观组织进行了表征，利用电子万能拉伸试验机测试了其力学性能。结果表明，电解铝液中未添加固体冷料时，铝合金熔体含氢量高，约为0.162 ml/(100 g Al)，铸轧板局部晶粒粗大，并且产生局部严重偏析现象，力学性能差；随着固体冷料占比增加，铝合金熔体含氢量逐渐降低，铸轧板偏析逐渐减弱，铸轧板晶粒尺寸减小，分布趋于更均匀，力学性能逐渐改善；当固体冷料占比为30%~70%时，铝合金熔体平均含氢量低于0.108 ml/(100 g Al)，铸轧板晶粒细小均匀，未发现明显偏析现象，其抗拉强度不低于128.3 MPa，断后伸长率不低于38.0%，铝合金铸轧板组织性能达到较佳匹配。

Effect of Solid Cold Material Ratio on Microstructure and Properties of Cast-rolling Plate for Double Zero Aluminum Foil

In order to optimize the proportion of solid cold material in electrolytic aluminum solution and stably obtain high-quality aluminum alloy melt, taking 8079 aluminum alloy as the research object, the hydrogen content in aluminum alloy melt with different solid material proportions (0%, 20%, 30%, 40%, 60%, 70%) during electrolytic aluminum liquid casting and rolling production was measured by ABB hydrogen meter, the microstructure of cast-rolling plate for double zero aluminum foil was characterized by optical microscope (OM),scanning electron microscope (SEM) and energy spectrum analyzer (EDS). Its mechanical properties were tested by electronic universal tensile testing machine.The results show that when no solid material is added to the electrolytic aluminum solution, the hydrogen content in the aluminum alloy melt is high, about 0.162 ml/(100 g Al), the local grain of the cast rolling plate is coarse, the local serious segregation phenomenon occurs, and the mechanical properties are poor.With the increase of the proportion of solid material in electrolytic aluminum solution, the hydrogen content in aluminum alloy melt first decreases and then increases, the segregation of cast rolling plate first weakens and then increases, the grains of cast rolling plate are finer and more uniform, and the mechanical properties are gradually improved.When the proportion of solid cold material is 30% ~ 70%, the average hydrogen content of aluminum alloy melt is less than 0.108 ml / (100 g Al), the grains of cast rolling plate are fine and uniform, no obvious segregation is found, the tensile strength is not less than 128.3 MPa, the elongation after fracture is not less than 38.0%, and the microstructure of aluminum alloy cast rolling plate can achieve a better match.