环氧基Sn-Bi焊膏的焊点热稳定性  

Thermal Stability of Solder Joints of Epoxy-based Sn-Bi Solder Paste

作　　者：杨晓军[1] 李晓光 贺定勇[1] 马立民[1] YANG Xiaojun;LI Xiaoguang;HE Dingyong;MA Limin(Institute of Welding and Surface Engineering Technology,College of Materials Science and Engineering,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学材料科学与工程学院,焊接与表面工程技术研究所,北京100124

出　　处：《北京工业大学学报》2025年第2期140-147,共8页Journal of Beijing University of Technology

基　　金：国家自然科学青年基金资助项目(52205324);国家自然科学基金资助项目(51301007)。

摘　　要：为探究环氧树脂壳层对Sn-Bi焊点的热稳定性的影响,选取了130~170℃的温度区间,对自制环氧基Sn-Bi焊膏和商用Sn-Bi焊膏(不含可固化树脂)形成的焊点分别进行了热循环试验。结果表明,1 000次热循环后,环氧基Sn-Bi焊膏形成的焊点,其表面的环氧树脂壳层依然完整保留,而焊点与铜基板的界面金属间化合物的厚度也明显低于商用Sn-Bi焊膏。1 000次热循环后,环氧基Sn-Bi焊膏形成的焊点的电导率由1.90×10^(6) S/m降为7.96×10^(5) S/m,剪切强度由145.7 MPa降为123.7 MPa;商用Sn-Bi焊膏形成的焊点的电导率由1.94×10^(6) S/m降为4.95×10^(5) S/m,剪切强度由116.1 MPa降为97.3 MPa。因此,对比商用Sn-Bi焊膏,环氧基Sn-Bi焊膏形成的焊点表面的环氧树脂壳层对于提高焊点的剪切强度和热稳定性是有利的,且一定程度上抑制了金属间化合物的生长。To investigate the effect of the epoxy resin shell on the thermal stability of Sn-Bi solder joints,the temperature range of 130-170 ℃ was set and thermal cycling tests were carried out on solder joints formed by self-made epoxy-based Sn-Bi solder paste and commercial Sn-Bi solder paste(without curable resin).Results show that after 1 000 thermal cycles,the epoxy resin shell on the surface of the solder joints formed by the epoxy-based Sn-Bi paste remains intact and the thickness of the intermetallic compound between the solder joint and the copper substrate is also significantly lower than that of the commercial Sn-Bi solder pastes.The electrical conductivity of the solder joint formed by the epoxy-based Sn-Bi paste decreases from 1.90×10^(6) S/m to 7.96×10^(5) S/m after 1 000 thermal cycles,and the shear strength decreases from 145.7 MPa to 123.7 MPa.However,the electrical conductivity of the solder joint formed by the commercial Sn-Bi paste decreases from 1.94×10^(6) S/m to 4.95×10^(5) S/m,and the shear strength decreases from 116.1 MPa to 97.3 MPa.Therefore,compared with commercial Sn-Bi solder paste,the epoxy resin shell on the surface of the solder joint formed by epoxy-based Sn-Bi solder paste effectively improves the shear strength and thermal stability of the solder joint,and to some extent hinders the growth of intermetallic compounds.

关 键 词：无铅焊膏 环氧树脂 热稳定性 金属间化合物 电导率 剪切强度 

分 类 号：TG42[金属学及工艺—焊接]