热顶铸造中结晶器石墨环高度对铝铸锭质量的影响  

Effect of Graphite Ring Height on the Quality of Aluminum BilletsProduced by Using the Hot-top Casting Technology

作　　者：沈国新 刘金辉 李键安 陈康康 张迪 SHEN Guo-xin;LIU Jin-hui;LI Jian-an;CHEN Kang-kang;ZHANG Di(Guangdong Xingfa(Henan)Aluminum Co.,Ltd.,Jiaozuo 454500,China)

机构地区：[1]广东兴发铝业(河南)有限公司,焦作454500

出　　处：《铝加工》2020年第6期44-48,共5页Aluminium Fabrication

摘　　要：在热顶铸造的金属凝固过程中,铸锭表层经历一次冷却和二次冷却,引起晶界出现重熔,溶质流动重新分配,最终导致表层出现宏观偏析层。热顶铸造的核心部件是结晶器里的石墨环,它是影响铸锭表层宏观偏析的关键因素。由于铝液在结晶凝固过程中与石墨环直接接触,所以石墨环又会影响铸造工艺,从而影响铸锭表面质量。以6061合金ϕ320 mm规格圆铸锭为研究对象,分析不同石墨环高度对铸锭表面质量及表层成分偏析的影响,从而确定合理的结晶器石墨环高度。In hot top casting,the solidification process of ingot surface metal undergoes primary cooling and secondary cooling,which results in remelting of grain boundary first,redistribution of solute flow,and segregation layer on the surface.The core component of hot top casting is the graphite ring in the mould.Therefore,the graphite ring is the key factor affecting the surface segregation of ingot.Because of the direct contact with the graphite ring in the process of solidification,the graphite ring will affect the casting process and the surface quality of the ingot.Based on the research of 6061 alloyφ320mm round ingot,the influence of different height of graphite ring on the surface quality and composition segregation of ingot are analyzed,so as to determine the reasonable height of graphite ring in mold.

关 键 词：热顶铸造 石墨环 偏析层 圆铸锭表面质量 

分 类 号：TG292[金属学及工艺—铸造]