SiC基陶瓷与Q235A钢钎焊连接的接头组织与性能研究  

Study on structure and properties of the joint between SiC ceramic and Q235A steel through brazed connection

作　　者：韩春福 高天翔 吴坤 HAN Chunfu;GAO Tianxiang;WU Kun(Shanxi Shanmei Coal Caojiatan Mining Co.Ltd.,Yulin 719001,Shanxi,China;School of Mechanical and Electrical Engineering,China University of Mining and Technology,Xuzhou 221116,Jiangshu,China)

机构地区：[1]陕西陕煤曹家滩矿业有限公司,陕西榆林719001 [2]中国矿业大学机电工程学院,江苏徐州221116

出　　处：《贵金属》2024年第3期52-58,共7页Precious Metals

摘　　要：通过向Ag-26.88Cu-4Ti粉末中加入不同体积分数的TiN粉末,研究出一种适用于钎焊SiC(70%SiC+30%Si_(3)N_(4))陶瓷与Q235A钢的钎料组分配比及合适的钎焊工艺。通过扫描电子显微镜对焊缝微观界面组织进行观察,探讨钎料与SiC母材的连接机理,并通过剪切实验,测试其连接强度。结果表明,此种钎料具有良好的流动性,且钎料与SiC母材结合紧密,无明显孔洞现象,得到良好的连接层,所得的反应产物主要为TiC和Ti_(5)Si_(3);当钎料中的TiN体积分数不断增加时,钎料的流动性变差,当TiN体积分数为5%时,钎料具有最好的流动性;当钎焊温度过低时,钎料流动性差,造成连接强度低,当钎焊温度过高时,生成过厚的Ti_(5)Si_(3)脆相;综合研究发现,当加入5%TiN(体积分数)粉末、钎焊温度为920℃、保温时间为10 min时,焊接效果最好,钎焊接头得到最大剪切应力,为85.6 MPa。A brazing material and process suitable for brazing SiC(70%SiC+30%Si_(3)N_(4))ceramics and Q235A steel together were developed by adding different volume fractions of TiN powders into Ag-26.88Cu-4Ti powders.The microstructure of the weld interface was observed by scanning electron microscope,and the connection strength was tested through shear experiments.The connection mechanisms between solder and SiC base metal were explored.The experimental results indicated that this type of brazing material had good flowability and was tightly bonded to the SiC base material without obvious pores,forming a good connection layer.The reaction products were found to be mainly TiC and Ti_(5)Si_(3).The brazing material displayed the best flowability when the volume fraction of TiN reached 5%.Futher increase in the volume fraction led to a decrease of the flowability of the brazing material Too low brazing temperature would compromise the fluidity of the brazing material,resulting in low connection strength,wheras brazing at a high temperature would give rise to an excessive thickness of Ti_(5)Si_(3) brittle phase.Comprehensive research demonstrated that the best welding results could be achieved by adding 5%TiN powder and brazing at 920℃for 10 minutes,and the maximum shear stress of the brazed joint would be up to 85.6 MPa.

关 键 词：陶瓷 金属 钎焊 复合钎料 剪切强度 

分 类 号：TG454[金属学及工艺—焊接]