Effects of trace amount praseodymium and neodymium on microstructure and mechanical properties of Sn–0.3Ag–0.7Cu–0.5Ga solder
- 172 Downloads
The effects of trace mount of rare earth elements Pr and Nd addition on Sn–0.3Ag–0.7Cu–0.5Ga lead free solder were investigated by observation of microstructure and the morphology of interface layer, as well as the test of shearing strength of the solder joints. The results show that the microstructure of the solder matrix can be optimized by appropriate addition of Pr and Nd, but the scalloped and “region-like” compounds (IMCs) appear in the solder matrix with excessive Pr and Nd addition respectively which may result in the stress concentration and become the birthplace of the cracks. The behavior of absorption of rare earth elements can retard the interface reaction between solder and Cu substrate, refine the morphology of the interface layer. The shearing strength of the solder joints can be enhanced better with appropriate addition of Pr than Nd by improvement of nucleation rate and control of growth rate of the grains near the interface layer.
KeywordsShear Strength Solder Joint Interface Layer Solder Matrix Shear Strength Test
The Project was supported by the Key Laboratory of Advanced Welding Technology of Jiangsu Province, China (Foundation No. JSAWT-14-04). This work was also supported by the Fundamental Research Funds for the Central Universities and the Foundation of Graduate Innovation Center in NUAA (Foundation No. kfjj20150604) and this work was also supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).
- 3.D.X. Luo, S.B. Xue, S. Liu, Investigation on the intermetallic compound layer growth of Sn–0.5Ag–0.7Cu-xGa/Cu solder joints during isothermal aging. J. Mater. Sci.: Mater. Electron. 25(12), 5195–5200 (2014)Google Scholar
- 4.G. Zeng, S.B. Xue, L. Zhang et al., A review on the interfacial intermetallic compounds between Sn–Ag–Cu based solders and substrates. J. Mater. Sci.: Mater. Electron. 21(5), 421–440 (2010)Google Scholar
- 7.W.X. Chen, S.B. Xue, H. Wang et al., Investigation on properties of Ga to Sn–9Zn lead-free solder. J. Mater. Sci.: Mater. Electron. 21(5), 496–502 (2010)Google Scholar
- 8.D.X. Luo, S.B. Xue, Z.Q. Li, Effects of Ga addition on microstructure and properties of Sn–0.5Ag–0.7Cu solder. J. Mater. Sci.: Mater. Electron. 25(8), 3566–3571 (2014)Google Scholar
- 9.Q. He, R.G. Ren, X.P. Zhao, Modification of Sn Ag Cu Ga filler metals for electronic packaging. Electron. Packag. 7, 14–15 (2014)Google Scholar
- 10.Kang I. Chen, Shou C. Cheng, Chin H. Cheng et al., The effects of gallium additions on microstructures and thermal and mechanical properties of Sn–9Zn solder alloys. Adv. Mater. Sci. Eng. 26(4), 653–659 (2014)Google Scholar
- 11.L.L. Gao, S.B. Xue, H. Xu, Microstructure and properties of SnAgCu-xPr solder. Trans. China Weld. Inst. 33(1), 69–72 (2012)Google Scholar
- 12.L.L. Gao, S.B. Xue, L. Zhang et al., Effects of trace rare earth Nd addition on microstructure and properties of SnAgCu solder. J. Mater. Sci.: Mater. Electron. 21(7), 643–648 (2010)Google Scholar
- 15.X. Chen, J. Zhou, F. Xue et al., Microstructures and mechanical properties of Sn–0.1Ag–0.7Cu-(Co, Ni, and Nd) lead-free solders. J. Mater. Sci.: Mater. Electron. 44(2), 725–732 (2015)Google Scholar
- 16.J.D. Luo, S.B. Xue, H. Ye et al., Interfacial microstructure and properties of SnCuNi-xPr/Cu solder joint. Trans. China Weld. Inst. 33(5), 49–54 (2012)Google Scholar