(北京科技大学 材料科学与工程学院, 北京 100083)
摘 要: 研究了热-剪切循环条件下Sn-3.5Ag-0.5Cu钎料/Cu界面的显微结构, 分析了界面金属间化合物的生长行为, 并与恒温时效后的Sn-3.5Ag-0.5Cu/Cu界面进行了对比。 结果表明: 恒温时效至100 h, Sn-3.5Ag-0.5Cu/Cu界面上已形成Cu6Sn5和Cu3Sn两层金属间化合物; 而热-剪切循环至720周Sn-3.5Ag-0.5Cu/Cu界面上只存在Cu6Sn5金属间化合物层, 无Cu3Sn层生成, 在界面近域的钎料内, 颗粒状的Ag3Sn聚集长大成块状; 在热-剪切循环和恒温时效过程中, 界面金属间化合物的形态初始都为扇贝状, 随着时效时间的延长逐渐趋于平缓, 最终以层状形式生长。
关键字: 热-剪切循环; 恒温时效; Sn-3.5Ag-0.5Cu/Cu界面; 金属间化合物
(School of Materials Science and Engineering,
University of Science and Technology Beijing, Beijing 100083, China)
Abstract: The microstructure of Sn-3.5Ag-0.5Cu/Cu interface after thermal-shearing cycling was investigated. Compared with Sn-3.5Ag-0.5Cu /Cu interface after isothermal aging, the development of interfacial IMC during thermal-shearing cycling was studied too. The results show that Cu6Sn5 and Cu3Sn IMC layers have formed at the interface of Sn-3.5Ag-0.5Cu/Cu after isothermal aging for 100 h, while only Cu6Sn5 IMC layer, no Cu3Sn layer, presents at the Sn-3.5Ag-0.5Cu/Cu interface after thermal-shearing cycling for 720 cycles, and particle-like phase Ag3Sn grows into massive phase in the field near to the interface. The interfacial IMC exists as scallop-like in the initial aging, during either thermal-shearing cycling or isothermal aging. Then they gradually grow up to planar-like with the aging time increasing.
Key words: thermal-shearing cycling; isothermal aging; Sn-3.5Ag-0.5Cu/Cu interface; intermetallic compound (IMC)