超高纯AlSi1铸锭反偏析研究  

Research on Negative Segregation of High Purity AlSi1 Cast Ingot

作　　者：尚再艳[1,2] 刘红宾[1,2] 陈明[1,2] 杨宇辉 

机构地区：[1]北京有色金属研究总院,北京100088 [2]有研亿金新材料股份有限公司,北京102200

出　　处：《热加工工艺》2013年第9期46-47,50,共3页Hot Working Technology

基　　金：国家863课题(2008AA031802)

摘　　要：通过实验研究了AlSi1铸锭反偏析现象。采用真空感应炉熔炼、石墨模铸造获得高纯AlSi1合金铸锭。利用电感耦合等离子体发射光谱仪分析铸锭中Si成分分布,采用间隙气体分析法分析铸锭气体含量,使用光学显微镜观察了铸锭金相组织。研究发现,铸锭含气量非常低的情况下,铸锭底部、中部和顶部的截面圆内都存在着明显的反偏析,铸锭中部心部区域的Si含量最低。铸锭的边部为尺寸较小的柱状晶,中部为粗大的柱状晶,细小Si析出相弥散分布,心部为等轴晶,Si析出相主要聚集在晶界附近,呈棒状,且尺寸明显长大。AlSi1熔体凝固时,先析出相Si的不断形核与长大消耗大量的Si,使得后凝固熔体贫Si,从而导致了铸锭的反偏析缺陷。The negative segregation of high purity AISi 1 cast ingots was studied.The high purity A1Si 1 cast ingots were gotten in vacuum induction melting furnace. The Si contents of ingots were analyzed by ICP-AES and the gas content was analyzed by IGA. The microstructure was observed by optical microscope. The results show that the negative segregation presents in cast ingots even though the gas contents are very low. The diameters of columnar crystals in the edge of cross-section of ingots are about 500μm. The coarse columnar crystals are in the middle and equaix crystals are in the center. The precipitated phase Si disperses in matrix and bright crystals present in the center.

关 键 词：高纯AlSi1 反偏析 析气 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG245[金属学及工艺—金属材料]