高熔点差三元合金累积叠轧-扩散合金化制备工艺  

High Difference Melting Point of Ternary Alloy by Accumulative Roll Bonding-Diffusion Alloying Preparation Process

作　　者：王文静[1,2,3] 冯启航 刘雪峰[1,2,3] 涂英明 Wang Wenjing;Feng Qihang;Liu Xuefeng;Tu Yingming(Beijing Advanced Innovation Center for Materials Genome Engineering,University of Science and Technology Beijing,Beijing 100083,China;Beijing Laboratory of Metallic Materials and Processing for Modern Transportation,University of Science and Technology Beijing,Beijing 100083,China;Key Laboratory for Advanced Materials Processing,Ministry of Education,University of Science and Technology Beijing,Beijing 100083,China;Baoshan Iron&Steel Co.,Ltd,Shanghai 201900,China)

机构地区：[1]北京科技大学北京材料基因工程高精尖创新中心,北京100083 [2]北京科技大学现代交通金属材料与加工技术北京实验室,北京100083 [3]北京科技大学材料先进制备技术教育部重点实验室,北京100083 [4]宝山钢铁股份有限公司,上海201900

出　　处：《稀有金属材料与工程》2023年第8期2765-2774,共10页Rare Metal Materials and Engineering

基　　金：国家重点研发计划(2018YFA0707300);国家自然科学基金(51904029,52127802)。

摘　　要：为解决高熔点差多元合金制备方法存在的元素偏析、合金性能受限、制备成本高等问题,提出了高熔点差组元合金的累积叠轧-扩散合金化(ARB-DA)制备新工艺。采用SEM、EDS、TEM、XRD和万能试验机表征了累积叠轧-扩散合金化Cu-21Ni-5Sn合金的组织和性能,研究了累积叠轧和阶梯式扩散热处理工艺对Cu-21Ni-5Sn合金成分均匀性的影响和机理,并揭示了后续时效制度对Cu-21Ni-5Sn合金性能的影响和机理。结果表明:通过累积叠轧7道次+650℃/5 h+1000℃/8 h阶梯真空扩散热处理工艺,制备出了元素误差小于5%、成分均匀的Cu-21Ni-5Sn合金。采用累积叠轧实现减薄中间层、缩短扩散距离,增加晶界、位错等原子扩散通道,低熔点Sn元素与Cu、Ni元素在650℃形成高熔点(Cu,Ni)_(3)Sn金属间化合物临界层,在1000℃高温加速Cu、Ni元素扩散。Cu-21Ni-5Sn合金在40%预冷变形下于470℃时效60 min充分调幅分解,基体中析出致密的与基体共格的DO22及L12有序固溶体,与α铜基体之间的取向关系为(111)_(Cu)//(220)_(DO_(22)),(200)_(Cu)//(310)_(l1_(2))。合金抗拉强度达到峰值925 MPa,弹性模量为135.4 GPa,合金导电率达到6.23%IACS。In order to solve the problems of elemental segregation,limited properties and high cost in the preparation of multi-alloys with high difference of multi-alloys melting point,a new process of accumulative roll bonding(ARB)-diffusion alloying(DA)has been developed.The properties of the ARB-DA Cu-21Ni-5Sn alloy were characterized by SEM,EDS,TEM,XRD and the universal testing machine.The effects and mechanisms of the ARB and step diffusion heat treatment processes on the compositional homogeneity of the Cu-21Ni-5Sn alloy were investigated,and the effects and mechanisms of the subsequent aging regime on the properties of the Cu-21Ni-5Sn alloy were revealed.The results show that Cu-21Ni-5Sn alloy with elemental error of less than 5%and homogeneous composition was prepared by ARB(7 passes+650°C/5 h+1000°C/8 h)and step vacuum diffusion heat treatment process.Cumulative rolling is used to reduce the intermediate layer,shorten the diffusion distance,and increase the atomic diffusion channels such as grain boundaries and dislocations.The low melting point Sn elements form a high melting point(Cu,Ni)3Sn intermetallic compound critical layer with Cu and Ni elements at 650°C,and the diffusion of Cu and Ni elements is accelerated at 1000°C.The Cu-21Ni-5Sn alloy was aged at 470°C for 60 min under 40%pre-cooling deformation for 60 min for fully spinodal decomposition.Dense DO22 and L12 ordered solid solutions are precipitated,and the orientation relationship between these solid solutions and the matrix withα-Cu matrix is (111)_(Cu)//(220)_(DO_(22)),(200)_(Cu)//(310)_(l1_(2)),respectively.The as-prepared alloy has maximum tensile strength of 925 MPa,elastic modulus of 135.4 GPa,and conductivity of 6.23%IACS.

关 键 词：高熔点差合金 累积叠轧-扩散合金化 成分均匀化 时效 

分 类 号：TG33[金属学及工艺—金属压力加工]