( 大連理工大學(xué) 材料工程系， 大連 116023)
摘 要: 采用ST50潤濕實(shí)驗(yàn)儀完成了釬焊并研究分析了Sn-9Zn-3Bi/Cu 接頭在170℃下長期時效的顯微結(jié)構(gòu)變化。 結(jié)果表明： Sn-9Zn-3Bi/Cn接頭時效至200h后在界面處形成單一連續(xù)的Cu5Zn8化合物層；時效至500h和1000h后， 界面處形成了3層化合物層， 從銅母材側(cè)起， 分別為Cu-Sn化合物層， Cu-Zn化合物層和Sn-Cu化合物層； 隨著時效時間的增加， 整個金屬化合物層變厚，而Cu-Zn化合物層減薄， 表明Cu-Zn化合物層在時效過程中具有不穩(wěn)定性。
關(guān)鍵字: 無鉛釬料； Sn-Zn-Bi；顯微結(jié)構(gòu)； 界面反應(yīng)； 金屬間化合物
（ Department of Materials Engineering,
Dalian University of Technology, Dalian 116023, China）
Abstract: Soldering process was performed by wetting test machine ST50. The microstructures of Sn-9Zn-3Bi/Cu joint were investigated under 170℃ thermal exposure conditions. The results show that a continuous single layer of Cu5Zn8 intermetallic compound appears when aging within 200h and three layers are formed after aging for 500h and 1000h. From the Cu substrate, they are Cu-Sn layer, Cu-Zn layer, Sn-Cu layer, respectively. The total intermetallic compound layers thicken while the thickness of Cu-Zn compound layer decreases with increasing exposure time. It indicates that the Cu-Zn compounds are not stable during long-term aging.
Key words: lead-free solder; Sn-Zn-Bi; microstructure; interface reaction; intermetallic compound
