Li Zhigang, Cheng Kai, Liu Jiajun, He Yigang, Xiao Yong
School of Electronic Engineering and Automation, Hefei University of Technology, Hefei 230009, China.
School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China.
Materials (Basel). 2023 Jul 26;16(15):5253. doi: 10.3390/ma16155253.
Ni-xCu/Sn soldering joints were aged at 200 °C, and the microstructure evolution and mechanical properties during the solid-state reaction were studied under shear loading. Results showed that the intermetallic compounds (IMCs) exhibited a Cu content-dependent transformation from the (Ni,Cu)Sn phase to the (Cu,Ni)Sn phase at the Ni-xCu/Sn interface. Furthermore, a CuSn layer was observed exclusively at the Cu/Sn interface. The shear strength of the soldering joints after thermal aging exhibited an initial decrease followed by an increase, except for a significant enhancement at the Cu content of 60 wt.%. In addition, the evolution law of mechanical properties and failure mechanism of the thermal aging joints were elucidated based on the fracture microstructure and the fracture curve of the joints.
镍铜/锡焊点在200°C下时效处理，并在剪切载荷下研究了固态反应过程中的微观结构演变和力学性能。结果表明，金属间化合物（IMC）在镍铜/锡界面处呈现出铜含量依赖的从（镍，铜）锡相到（铜，镍）锡相的转变。此外，仅在铜/锡界面处观察到一个铜锡层。热时效后焊点的剪切强度呈现出先下降后上升的趋势，除了在铜含量为60 wt.%时显著增强。此外，基于焊点的断裂微观结构和断裂曲线阐明了热时效焊点力学性能的演变规律和失效机制。
