摘要: |
研究了150 ℃时效条件下,经过360,720以及3 000 h以上时效处理后Sn-Zn-Nd钎料焊点界面组织的变化. 结果表明,焊点在长期时效过程中界面层成分的变化主要由原子的扩散机制主导,随着界面附近各原子浓度的变化,界面层的成分从焊后的单一Cu5Zn8层逐渐转变为成分复杂的Cu-Zn-Sn多元结构. 在时效过程中,由于界面层体积的增加会受到钎料基体的阻碍,因此在界面两侧的晶界处产生了压应力. 这些应力在时效过程中不断累积,当累积到一定程度后,使得金属间化合物层表面出现了孔洞和裂纹,从而导致了焊点性能的恶化. |
关键词: 时效处理 焊点 界面 金属间化合物 |
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基金项目:新型钎焊材料与技术国家重点实验室开放课题资助项目(SKLABFMT201604) |
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Transformation of interfacial microstructure in aged Sn-Zn-Nd solder joint |
XUE Peng1, WANG Kehong1, ZHOU Qi1, HE Peng2, LONG Weimin3, ZHONG Sujuan3
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1.School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China;2.State Key Laboratory of Welding and Joining, Harbin Institute of Technology, Harbin 150001, China;3.State Key Laboratory of Advanced Brazing Filler Metals & Technology, Zhengzhou Research Institute of Mechanical Engineering, Zhengzhou 450001, China
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Abstract: |
The interfacial microstructure in Sn-Zn-Nd solder joint aged at 360 hours, 720 hours, and 3 000 hours was investigated respectively. The results indicated that the transformation of interfacial intermetallic compound layer was dominated by the atom diffusion. After long-term aging, the composition of intermetallic compound layer transformed from Cu5Zn8 into a mixed Cu-Zn-Sn compounds. During the aging process, the diffusion-induced stresses also accumulated at the interface between solder matrix and Cu pad. When it reached a certain value, voids and fractures was formed in the intermetallic compound layer, which deteriorated the soldered joint properties. |
Key words: Sn-Zn solder joint interface intermetallic compound |