冷却速率对Al-2Cu-5Ni合金相组织及力学性能影响  

Effects of Cooling Rate on Phase Structure and Mechanical Properties of Al-2Cu-5Ni Alloy

作　　者：田皓 彭渝丽[1,2] 袁满 崔文[1,2] 王建利 郭永春[1,2] 杨忠 Tian Hao;Peng Yuli;Yuan Man;Cui Wen;Wang Jianli;Guo Yongchun;Yang Zhong(School of Materials and Chemical Engineering,Xi'an Technological University;Shaanxi Magnesium Aluminum Light Alloy Composite Engineering Research Center;CSIC NO.12 Research Institute)

机构地区：[1]西安工业大学材料与化工学院 [2]陕西省镁铝轻合金复合材料工程研究中心 [3]中国船舶重工集团公司第十二研究所

出　　处：《特种铸造及有色合金》2023年第12期1705-1709,共5页Special Casting & Nonferrous Alloys

基　　金：陕西省重点研发计划资助项目(K20200036,2021LLRH-05-08);陕西省科技厅自然科学基础研究计划资助项目(2022JM-239)。

摘　　要：通过相图热力学计算设计了平衡凝固组织仅为α-Al基体和Al_(3)CuNi相的Al-2Cu-5Ni合金,研究了冷却速率对铸态合金组织及力学性能的影响。结果表明,随着冷却速率的提高,α-Al晶粒尺寸减小。当冷却速率由3.05℃/s提升到5.58℃/s时,Al_(3)CuNi相由鱼骨团簇组织转变为颗粒团簇状,冷却速率提高至9.08℃/s时,Al_(3)CuNi相转变为短条状,合金室温抗拉强度和伸长率达到最大值,分别为218 MPa和16.15%;350℃、25 MPa稳态蠕变速率最低为2.56×10^(-5)s^(-1),蠕变机制为位错攀移。相比较冷却速率为3.05℃/s合金,抗拉强度、伸长率和抗蠕变性能分别提高了11%、37%和96%。An Al-2Cu-5Ni alloy only containingα-Al and Al_(3)CuNi phases as equilibrium solidification structure was designed by thermodynamic phase diagram calculation,and effects of cooling rate on microstructure and mechanical properties of as-cast Al-2Cu-5Ni alloy were investigated.The results indicate that the grain size is decreased with cooling rate increase.The morphology of Al_(3)CuNi phase is transformed from fish-bone cluster to particle cluster as the cooling rate increasing from 3.05℃/s to 5.58℃/s,which is converted to short strip form with cooling rate further increasing to 9.08℃/s.Meanwhile,the tensile strength and elongation at room temperature reach the maximum value,which is 218 MPa and 16.15%,respectively.The minimum steady-state creep rate is achieved at 350℃under the stress of 25 MPa,which is 2.56×10^(-5)s^(-1),and creep mechanism is dislocation climbing.The tensile strength,elongation and creep resistance of the alloy are improved by 11%,37%and 96%,respectively,compared with those of the alloy prepared at cooling rate of 3.05℃/s.

关 键 词：Al-Cu-Ni合金 冷却速率 组织演变 力学性能 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG244.3[金属学及工艺—金属材料]