BNi6+9%Cu复合钎料真空钎焊纯铁的组织分析  

Analysis on microstructure of vacuum brazing for pure Fe by BNi6 & 9%Cu composite filler

作　　者：苌文龙[1] 于治水[1] 杨橄生[1] 姜鹤明[1] 

机构地区：[1]上海工程技术大学材料工程学院,201620

出　　处：《焊接》2013年第3期42-44,71,共3页Welding & Joining

基　　金：上海市教委科技创新项目(12ZZ186);上海市教委一流学科(机械工程)建设项目(YLJX12-2);浙江省钎焊材料与技术重点实验室开放基金项目资助(1002)

摘　　要：采用BNi6+9%Cu复合钎料真空钎焊纯Fe,研究了不同钎焊工艺对焊接接头组织的影响。通过金相试验、扫描电镜及能谱仪等设备观察了接头钎缝形貌,分析了组织成分。结果表明:BNi6+9%Cu钎料真空钎焊纯Fe,当钎焊温度较低时,由于钎料中添加熔点较高的Cu元素及母材Fe、的溶解,钎料流动性下降。由于钎料外置,液态钎料填缝过程中与母材的动态冶金作用使不同钎缝处的成分不同,则对接头组织的有较大的影响。钎缝头部反应剧烈,扩散区中柯肯达尔孔洞较多,且在Ni-P金属间化合物中容易形成裂纹;而在钎缝尾部金属间化合物呈岛状,两侧孔洞明显减少,未发现裂纹。综合分析,BNi6+9%Cu复合钎料真空钎焊纯铁在钎焊温度950℃、钎焊间隙30μm的钎焊工艺下,能够得到流动性好、柯肯达尔孔洞和裂纹较少的钎焊接头。Vacuum brazing of pure Fe with BNi6 & 9%Cu composite filler was carried out at different brazing temperature and assembling clearances.Microstructure and element distribution of the joints were identified by optical microscopy,scanning electron microscopy and energy dispersive spectrometry.The results show that the BNi6 & 9%Cu composite filler declines its fluidity because of the higher melting point of Cu and the dissolution of Fe in the experiments,especially for the lower brazing temperature.On the other hand,external solder leads to the different composition at different positions of brazes seam because of the dynamic metallurgy of welding process.The front part of brazed seam reacts sufficiently.A large quantity of Kirkendall voids in diffusion zone and cracks in Ni-P intermetallic compound were found.However,the intermetallic compounds presented island- type in the end part.What's more,the Kirkendall voids reduced significantly and cracks disappeared.Comprehensive analysis indicates that BNi6 & 9%Cu composite filler vacuum brazing of pure Fe can obtain better liquidity,less Kirkendall voids and cracks at brazing temperature of 950 ℃ and assembling clearance of 30μm.

关 键 词：BNi6+9%Cu 复合钎料 纯Fe 金属间化合物 

分 类 号：TG454[金属学及工艺—焊接]