不同碳含量对银钎料钎焊性能的影响  

Brazing Properties of Silver Based Filler Metal with Different Carbon Contents

作　　者：张冠星[1] 龙伟民[1] 何鹏[2] 崔艳艳[3] 佘春[1] 

机构地区：[1]郑州机械研究所新型钎焊材料与技术国家重点实验室,河南郑州450001 [2]哈尔滨工业大学先进焊接与连接国家重点实验室,黑龙江哈尔滨150001 [3]河南质量工程职业学院,河南平顶山467000

出　　处：《稀有金属》2015年第6期527-532,共6页Chinese Journal of Rare Metals

基　　金：国家科技部"863"计划项目(2012AA040208);郑州市重大科技专项(121PZDZX001)资助

摘　　要：通过不同的轧制工艺获得表层含碳量不同的钎料合金,采用金相显微镜（OM）、扫描电镜（SEM）、X射线衍射（XRD）等分析手段对其进行钎焊性能研究。结果表明,有油轧制的钎料会在其表面残留一层厚度约为0.5-7.0μm含碳层;碳在钎料表面主要以游离的碳分子和Zn C8,C2Cd O4形式存在;随着碳含量的增加（0%-1%）,钎料在基体上的润湿及抗拉强度逐渐降低,润湿面积由356.8 mm2降低到65.3mm2,抗拉强度由387.2 MPa降低到89.5 MPa,得出钎料中的碳含量应控制在0.005%以下;观察钎料润湿和焊接后界面,钎料表面的含碳层存在几种不同的形式,部分碳分子来不及上浮到表面而被包裹在钎料内部,在其内部成为游离的碳分子;部分碳分子随着钎料的熔化开始上浮,处于钎料周围,随着钎料的熔化铺展,这些碳分子颗粒被液态钎料推到了铺展的最前沿,在液态钎料周围形成一个包围圈;还有部分碳原子扩散到钢基体中,与钢中的铬、镍、铁等形成碳化物。Brazing properties of silver based brazing filler metal with different carbon contents obtained by different rolling technolo- gies were researched using optical microscopy （OM）, scanning electron microscopy （SEM）, X-ray diffraction （XRD）, etc. The re- suits showed that the carbon-containing layer was about O. 5 - 7.0 txm on the surface of brazing filler metal rolled with oil; the existing forms of carbon on the surface were mainly free carbon molecules, ZnCs and C2CdO4 ; with the carbon content increasing from 0% to 1.1% , the wetting area decreased from 356.8 to 65.3 mm2 , and the tensile strength decreased from 387.2 to 89.5 MPa. The carbon content in the brazing filler metal should be controlled below 0. 005%. There were several existing forms for surface carbon-contai- ning layer after brazing. Some carbon molecules which had no enough time to rise to the surface were wrapped inside the brazing filler metal ; some carbon molecules which floated with the melt of brazing filler metal were around the brazing filler metal, and then were pushed to the spreading forefront to form an annular ring; some diffused into the steel matrix to form carbides with Cr, Ni, Fe, etc.

关 键 词：残留碳 润湿性 抗拉强度 游离碳 碳化物 

分 类 号：TG425[金属学及工艺—焊接]