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论文类型：期刊论文

发表时间：2009-05-01

发表刊物：JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY

收录刊物：SCIE、EI、ISTIC、Scopus

卷号：25

期号：3

页面范围：410-414

ISSN号：1005-0302

关键字：Lead-free solder; Interfacial reaction; Intermetallic compounds; Aging

摘要：The wetting property of (Sn-9Zn)-2Cu (wt pct) on Ni substrate and the evolution of interfacial microstructure in (Sn-9Zn)-2Cu/Ni joints during soldering as well as isothermal aging were studied. The wetting ability of eutectic Sn-9Zn solder on Ni substrate was markedly improved by adding 2 wt pct Cu into this solder alloy. Plate-like Cu5Zn8 intermetallic compounds (IMCs) were detected in (Sn-9Zn)-2Cu solder matrix. A continuous Ni5Zn21 IMC layer was formed at (Sn-9Zn)-2Cu/Ni interface after soldering. This IMC layer kept its type and integrality even after aging at 170 degrees C for up to 1000 h. At the early aging stage (before 500 h), the IMC layer grew fast and its thickness followed a linear relationship with the square root of aging time. Thereafter, however, the thickness increased very slowly with longer aging time. When the joints were aged for 1000 h, a new IMC phase, (Cu,Ni)(5)Zn-8, was found in the matrix near the interface. The formation of (Cu,Ni)(5)Zn-8 phase can be attributed to the diffusion of Ni atoms into the solder matrix from the substrate.