微量Sc和Y对Al-0.2Ce合金线材微观组织与性能的影响  

Effect of traces of Sc and Y on the microstructure and properties of Al-0.2Ce alloy wire

作　　者：林耿 王维裔 喻艺 刘竝 潘清林 LIN Geng;WANG Wei-yi;YU Yi;LIU Bing;PAN Qing-lin(Light Alloy Research Institute of Central South University,Changsha 410083,China;School of Materials Science and Engineering,Central South University,Changsha 410083,China)

机构地区：[1]中南大学轻合金研究院,湖南长沙410083 [2]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《轻合金加工技术》2022年第3期38-46,共9页Light Alloy Fabrication Technology

基　　金：广东省重点领域研发计划资助(2020B010186002)。

摘　　要：采用熔铸一►均匀化—热挤压—冷拉拔—退火工艺制备出Ф4mm的Al-0.2Ce-zSc-yY合金线材,研究了微量Sc、Y对合金晶粒组织、相组成、亚结构及电导率、拉伸性能的影响。结果表明:加人微量Sc和Y后,消除了铸态Al-0.2Ce合金的枝晶,促进了等轴晶粒的形成,Al-0.2Ce-0.2Sc-0.1Y合金的平均晶粒尺寸为142.5μm。与AAl-0.2Ce-0.2Sc合金相比,Al-0.2Ce合金主要第二相Al_(13)Fe_(3)Ce相的尺寸和比例较大。添加Sc形成了纳米尺寸Al_(3)Sc析出相,晶粒内部亚晶界增多,提高了合金的强度和塑性。在此基础上添加微量Y,优化了第二相的析出形貌及分布,降低了合金的缺陷密度,改善了合金的综合性能。冷拉拔和退火后Al-0.2Ce-0.2Sc-0.1Y合金的抗拉强度、伸长率和导电率分别达到198 MPa、8.5%和61.77%IACS,具有优良拉伸性能和导电性能。The Al-0.2Ce-xSc-yY alloy wire ofФ4 mm was prepared by melting and casting—►homogenization—>>hot extrusion→cold drawing→annealing process,and the effects of trace Sc and Y on the grain morphology,the second phases,substructures and electrical conductivity and tensile properties of the alloy were studied.The results show that the addition of trace amounts of Sc and Y eliminates the dendrites of the as-cast Al-0.2Ce alloy and promotes the formation of equiaxed grains,and the average grain size of the Al-0.2Ce-0.2Sc-0.1Y alloy is 142.5|xm.As the size and proportion of the second main phase of Al-0.2Ce alloy,namely Al_(13)Fe_(3)Ce phase,are larger than those of Al-0.2Ce-0.2Sc alloy.The addition of Sc forms a nano-sized Al_(3)Sc precipitation phase with increased subgrain boundaries inside the grains,which enhances the strength and elongation.The addition of traces of Y optimizes the precipitation morphology and distribution of the second phases,reduces the defect density of the alloy,and improves the performances of the alloy.The tensile strength,elongation and electrical conductivity of Al-0.2Ce-0.2Sc-0.1Y alloy after cold drawing and annealing reach 198 MPa,8.5%and 61.77%IACS,respectively,which achieve excellent tensile properties and high electrical conductivity.

关 键 词：Al-0.2Ce合金 Al-0.2Ce-0.2Sc合金 Al-0.2Ce-0.2Sc-0.1Y合金 高强高导耐热铝合金 

分 类 号：TG146.21[一般工业技术—材料科学与工程]