AgCuZnMn钎焊CuAgZr合金接头的组织和性能  

Microstructure and Properties of BrazingJoint of CuAgZr AlloyUsing AgCuZnMn Braze Filler

作　　者：雷睿超 操齐高[2] 郑晶[2] 王瑞红 王国耀 Lei Ruichao;CaoQigao;Zheng Jing;Wang Ruihong;Wang Guoyao(Xi’an University of Technology,Xi’an 710048,China;Northwest Institute for Nonferrous Metal Research,Xi’an 710016,China)

机构地区：[1]西安理工大学,陕西西安710048 [2]西北有色金属研究院,陕西西安710016

出　　处：《稀有金属材料与工程》2021年第10期3720-3728,共9页Rare Metal Materials and Engineering

基　　金：国家重点研发计划(2017YFB0305702)。

摘　　要：本实验就高强高导Cu3Ag0.5Zr合金翅片与隔板的钎焊展开研究。使用Ag37.5Cu48.8Zn5.5Mn8.2(质量分数,%,下同)箔带作为钎料,对钎缝宽度为50~200μm的Cu3Ag0.5Zr合金接头进行钎焊,钎焊温度为840~900℃,保温时间为5~20min。通过水淬快速冷却的方法将保温阶段钎缝处固液界面形貌保留下来,利用扫描电镜和EDS能谱仪对接头钎缝组织和剪切断口形貌进行研究,利用万能力学试验机对接头剪切性能进行测试。研究表明:钎缝组织的形成经历了母材向钎料区溶解、富Cu相等温凝固和降温凝固3个阶段,形成了3种钎缝组织,分别为富Ag相呈网状分布于母材和钎料区富Cu相之间、钎料区AgCu共晶组织、共晶组织和富Cu相组成钎料区组织。另外,CuZr相分布于界面区和钎料区,钎料区中Mn固溶于富Ag相和富Cu相中,其中CuZr相和Mn元素与接头抗剪切强度有一定的相关性,钎缝组织中的CuZr相削弱了接头抗剪切强度,Mn元素则强化了接头剪切性能。钎焊温度、保温时间和钎缝宽度通过影响钎缝处钎焊组织、CuZr相尺寸及分布和钎料区Mn元素含量,影响接头抗剪切性能。当钎缝宽度为100μm,在870℃保温5min时,接头抗剪切强度达到最大,为308MPa。The brazing of Cu3Ag0.5Zr alloy fins and baffles wasstudied.Cu3Ag0.5Zr alloyjoint,with the brazing seam width of 50~200μm,was brazed using Ag37.5Cu48.8Zn5.5Mn8.2 braze fillerat 840~900℃for 5~20min.Solid-liquid interface morphology of the brazing joint at the insulationstage was retained by water quenching.The microstructureof the joints and shear fracture morphologywere studied by scanning electron microscope(SEM)and energy dispersive spectrometers(EDS),and the shear performanceof the joint was tested by universalmechanical testing machine.The results show that brazing joint structure has experiencedthree stagesincludingthe dissolution of the base material into the brazing filler metal area,the isothermal solidification of the Cu-rich phase,and the cooling and solidification.Three kindsof microstructures exist in jointswhich areAg-rich phase distributing in a network between the base metal and the Cu-rich phase,AgCu eutectic structure in joint gap,and the filler zone structure consisted of AgCu eutectic and copper-rich phase.Besides,CuZr phase distribute in the interface region and braze filler region,and Mn in the braze filler region is dissolved in Ag-rich phase and Cu-rich phase.CuZr in the brazing joint structure weakens the joint shear strength,meanwhile Mn element strengthens the joint shear performance.Shear strength of joint isaffected in the way that brazing temperature,holding time and filler thickness control the brazing seam structure,size and distribution of CuZr phaseand Mn concentration in filler area of joints.The maximum shear strength value,308MPa,isobtainedat 100μm thickness filler brazed at 870℃for5min.

关 键 词：Ag基钎料 CuAgZr合金 真空钎焊 接头强度 

分 类 号：TG454[金属学及工艺—焊接]