Fracture damage micro-mechanism of SnAgCu/Cu solder joint
The scallop-like Cu6Sn5 intermetellic compound (IMC) layer formed at the interface of Sn-3.8Ag-0.7Cu/Cu joint as soldered. These IMC layers graw during aging at 150℃. The fracture damage micro-mechanism of the joints is different when they have a different IMC thickness. When the thickness of IMC layer is less than 5.5μm,ductile fracture occurred in the solder. When it is more than 9μm,brittle fracture occurred between the solder and Cu. Scan Electronic Microscopy micro-analyses show that the fracture at the boundary could occur in one of following positions. One is the interface of Cu6Sn5 intermetallic compound and solder. Another is the cleavage intermetallic compound grains. The more thick the IMC layer,the more brittle the IMC,the lower the strength of the interface. The fracture position moved from solder inner to the interfacial Cu6Sn5 IMC layer with the IMC thickness increased. In addition,when aging for 480h,the Ag3Sn compound formed between solder and Cu6Sn5 compound. The strength of solder is also decreased during aging. The weakenhag of the solder matrix is caused by the coarsening of the eutectic solder structures. The weakening of the interracial IMC layer is caused by the size increase of the IMC grains and the decrease of connecting area of IMC layer and the solder.
Fracture damage Intermetalic compound Solder joint
Xiaohua Yang Xiaoyan Li Weizhen Dui
Instrumentation Analysis and Measurement Center,Fuzhou University,Fuzhou 350002,China School id Material Science and Engineering,Beijing University of Technology,Beijing 100022,China
国际会议
Fracture Mechanics and Applications 2008(国际断裂力学2008年年会)(FM2008)
杭州
英文
401-405
2008-10-31(万方平台首次上网日期,不代表论文的发表时间)