浅析晶粒细化剂对3102空调箔白条缺陷的影响

Effect of Grain Refiner on White Strip Defect of 3102 Aluminum Alloy Air-Conditioning Foil Stock

应用EPMA和EDS分析3102铝合金空调箔表面的白条缺陷,发现缺陷部位分布着大量TiB2聚集团,并通过分析同批次铸轧坯料内部组织,最终确定缺陷铝箔表面的TiB2聚集团由铸轧生产过程带入,在线加入的AlTi5B1晶粒细化剂中的TiB2因某些原因未充分参与结晶形核,在铸轧坯料内部形成TiB2聚集团,并在后续的箔轧过程中以非金属夹杂物的形式显露出来。研究表明,通过提高AlTi5B1晶粒细化剂加入点熔体温度和适当延长变质时间,选用优质的晶粒细化剂,将晶粒细化剂添加量控制在1.5~1.8 kg/t·Al,可以很好地预防晶粒细化剂造成的白条缺陷的产生。

EPMA and EDS were used to analyze the white stripe defects on the surface of 3102 aluminum alloy air-conditioning foil. It was found that a large number of TiB_(2) agglomerations were distributed in the defect area. By analyzing the internal structure of the same batch of roll-casting stock, it was finally determined that the TiB_(2) agglomerations on the surface of the defective aluminum foil were brought in by the roll-casting process.For some reasons, TiB_(2) in the on-line addition of AlTi5 B1 grain refiner did not fully participate in the crystallization nucleation, forming TiB_(2) agglomerations in the roll-casting stock, which were revealed in the foil rolling process in the form of non-metallic inclusions. The results show that by increasing the melt temperature at the addition point of AlTi5 B1 grain refiner and prolonging the inoculation time appropriately, selecting high-quality grain refiner and controlling the addition amount of grain refiner at 1.5~1.8 kg/t·Al, the white stripe defect caused by grain refiner can be well prevented.