界面反應
(哈爾濱工業(yè)大學 材料科學與工程學院 微連接研究室，哈爾濱 150001)
摘 要: 觀察了不同焊接工藝條件下釬焊接頭界面的微觀結構，并對釬焊過程中的界面反應進行分析。探討了釬縫界面處IMC的生長機制，通過對不同釬焊溫度和保溫時間下的IMC生長規(guī)律的分析建立銅錫化合物厚度與溫度和時間的關系方程。結果表明：釬焊過程中SnCu釬料合金鍍層與可焊性Cu層的界面處生成金屬間化合物Cu6Sn5和Cu3Sn；化合物的生長厚度與焊接時間之間滿足拋物線關系，表明化合物的生長為擴散反應控制過程，并隨焊接時間的延長化合物的生長速率逐漸下降。
關鍵字: SnCu釬料鍍層；Cu/Ni鍍層；金屬間化合物；釬焊；界面反應
alloy and Cu/Ni coatings during reflow soldering
TIAN Yan-hong, KONG Ling-chao
（Microjoining Laboratory, School of Materials Science and Engineering,
Harbin Institute of Technology, Harbin 150001, China）
Abstract:The interface microstructures of soldered joints under different soldering techniques were observed and analyzed. The interface reaction during soldering was studied. The growth mechanism of the IMCs was discussed and the influences of soldering temperature and dwell time on IMC evolution were investigated. The equation of the relationship between IMCs thickness and soldering conditions including soldering temperature and dwell time was developed. The results suggest that，during soldering, the joint interface between the solder and Cu/Ni coating exhibits a duplex structure of Cu6Sn5 and Cu3Sn intermetallic compounds (IMCs). A parabolic relationship exists between the growth of the IMC layer and soldering time. This indicates that the mechanism of IMC growth is a diffusion-controlled process. The growth rates for the intermetallic layers increase with soldering temperature, whereas decreases with time.
Key words: SnCu solder alloy coating; Cu/Ni coating; intermetallic compound; soldering; interfacial reaction
