钎焊温度对BNi-2非晶钎料钎焊1Cr18Ni9Ti不锈钢组织和性能的影响  

Effect of brazing temperature on microstructure and properties of 1Cr18Ni9Ti stainless steel brazed by amorphous BNi-2 filler

作　　者：田晓羽 张志伟[1] 周晨 赵连清[1] 田洋光 付伟[2] 宋晓国[2,3] TIAN Xiaoyu;ZHANG Zhiwei;ZHOU Chen;ZHAO Lianqing;TIAN Yangguang;FU Wei;SONG Xiaoguo(Beijing Institute of Control Engineering,Beijing,100190,China;National Key Laboratory of Precision Welding&Joining of Materials and Structures,Harbin Institute of Technology,Harbin,150001,China;Shandong Institute of Shipbuilding Technology,Weihai,264209,China)

机构地区：[1]北京控制工程研究所,北京100190 [2]哈尔滨工业大学材料结构精密焊接与连接全国重点实验室,哈尔滨150001 [3]山东船舶技术研究院,威海264209

出　　处：《焊接学报》2024年第6期61-67,共7页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(52175307,52105330);泰山学者工程专项经费资助项目(tsqn201812128)。

摘　　要：采用BNi-2非晶钎料成功钎焊了1Cr18Ni9Ti不锈钢,通过扫描电子显微镜及能谱仪对不同钎焊温度下钎焊接头的界面微观组织进行了表征及分析,并对钎焊接头的抗剪强度进行了测试,探究了钎焊温度对接头界面组织及力学性能的影响.结果表明钎焊接头的界面微观组织从钎缝中心到母材可以被分为3个区域,钎焊温度为1050℃时钎缝区主要为Ni基固溶体+Cr-B相,扩散区分布有Fe-Ni固溶体及细小条状的σ-FeCr相,晶间渗入区中奥氏体晶间处分布着σ-FeCr相及Cr-B相.随着钎焊温度的升高,B元素扩散速度不断加快,Cr-B相的晶间渗入程度加剧;钎缝中心的块状Cr-B相逐渐减小直至1150℃时消失,钎缝区组织均匀化.在温度的作用下,钎缝宽度呈现先减小后增大的趋势.而接头的抗剪强度呈先上升后下降的趋势;最大抗剪强度出现在1050℃时,约265 MPa;而接头的断裂形式主要以韧性断裂为主.利用阿伦尼乌斯方程得到了B原子的扩散活化能为8.18×10^(4)×nJ/mol,n为时间指数.1Cr18Ni9Ti stainless steel was successfully brazed with BNi-2 amorphous filler.The interfacial microstructure of brazed joints at different brazing temperatures was characterized and analysed by scanning electron microscope and energy dispersive spectrometer,and the shear strength of brazed joints was tested.The effect of brazing temperatures on the interfacial microstructure and mechanical properties of the joints was investigated.The results showed that the interfacial microstructure of brazed joints could be divided into three regions from the brazing seam centre to the base material,when the brazing temperature was 1050℃,the brazing seam region was mainly Ni-based solid solutions+Cr-B phases;the diffusion region was distributed with Fe-Ni solid solution and fine strips ofσ-FeCr phase;and in the intergranular infiltration region,the austenite grain boundaries were distributed with theσ-FeCr phases and the Cr-B phases.As the brazing temperature increased,the diffusion rate of B element was accelerated and the intergranular infiltration of Cr-B phases was intensified;the massive Cr-B phases in the centre of the braze were gradually reduced until they disappeared at 1150℃,and the microstructure of the braze area was homogenised.Under the effect of temperature,the width of the brazed joints showed a tendency to decrease and then increase.And the shear strength of the joints showed a tendency of increasing and then decreasing;the maximum shear strength appeared at 1050℃,about 265 MPa;and the fracture form of the joints was mainly dominated by ductile fracture.Using the Arrhenius equation the diffusion activation energy of the B atom was obtained as 8.18×10^(4)×n J/mol,with n being the time index.

关 键 词：钎焊 非晶钎料 微观组织 不锈钢 扩散激活能 

分 类 号：TG454[金属学及工艺—焊接]