半固态加工对Al-Cu合金中Cu元素分布的影响  

Effect of Semi-Solid Forming Process on the Distribution of Cu Elements in Al-Cu Alloy

作　　者：任鹤[1,2] 胡文全[1,3] 黄宏军[1] 胡冰[1,2] 袁晓光[1] 

机构地区：[1]沈阳工业大学材料科学与工程学院 [2]沈阳鼓风机集团 [3]辽宁工程技术大学

出　　处：《特种铸造及有色合金》2015年第5期490-494,共5页Special Casting & Nonferrous Alloys

基　　金：辽宁省第三批特聘教授支持计划资助项目

摘　　要：采用电磁搅拌法制备了Al-4Cu合金坯锭,对合金坯锭进行了二次加热重熔试验,分别研究了铸态、电磁搅拌态、二次加热重熔态合金中Cu元素的分布规律。结果表明,采用电磁搅拌方法制备的半固态坯锭存在Cu元素在晶界处富集现象,多晶交汇处富集最明显,晶粒内析出的含Cu金属间化合物数量少于未搅拌的;电磁搅拌强度越大,Cu元素在晶界处富集程度越明显;圆柱形坯锭沿径向由表面向心部的Cu元素富集程度逐渐增大。二次加热重熔改变了Cu元素在坯锭的分布,Cu元素分布与二次加热重熔的液相数量有关;重熔的液相数量较少时,Cu元素仍然在未重熔的固相之间富集,而重熔区内的Cu元素趋于均匀分布;重熔和未重熔区出现Cu元素平均含量的差值。Al-4Cu（mass fraction,% ）alloy billets were prepared by electromagnetic stirring,and rehea-ting melting experiment was carried out.The distribution of Cu elements was analyzed in the alloy bil-lets at as-cast,electromagnetic stirring and reheating melting condition,respectively.The results show that Cu element is segregated at the grain boundaries after electromagnetic stirring,especially at grain boundary junction.The number of precipitated Cu-contained compounds is less than that in the grains without electromagnetic stirring.With the increase of the magnetic field strength,segregation of Cu ele-ment becomes more serious increasingly,and the segregation of Cu element is increased from the surface to the core at radial direction of cylindrical billet.Reheating melting can change the distribution of Cu el-ement in the semi-solid billet,in which the degree of change is relevant to the fraction of remelting liquid volume.When the volume of remelting liquid is low,Cu elements still enrich in the non-remelting solid phases,while the distribution of Cu element will be uniform at the remelting zone.Reheating melting e-ventually enlarge the differences of Cu average content at remelting and non remelting zone.

关 键 词：半固态加工 AL-CU合金 元素富集 晶粒 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG249.26[金属学及工艺—金属材料]