The Relationship between XRD Peak Intensity and Mechanical Properties of Irradiated Lead-Free Solder

Abstract:

The variation on mechanical properties and crystalline structure of gamma-irradiated Sn-rich lead-free solder (SAC) were intensively investigated using nanoindentation and X-ray diffraction (XRD) techniques. Samples of solder on a printed circuit board (PCB) with copper substrate were irradiated at low dose (5 Gray) of gamma from Co-60 source. The nanoindentation hardness for β-Sn phase of the solder was found to increase from 0.1935 GPa to 0.2210 GPa after the irradiation. Furthermore XRD peak intensity was also observed to increase as well indicating the occurrence of defect in β-Sn crystal structure due to gamma radiation. The defect contributes to the increment of the hardness by indicating the change in crystallite size of the grains. Microstructure analysis by FESEM-EDAX has also confirmed the indentation was performed with no cracks in subsurface on β-Sn area.

• Periodical: Materials Science Forum (Volume 888)
• Pages: 423-427
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.888.423
• Online since: March 2017
• Authors: Wilfred @ Sylvester Paulus*, Irman Abdul Rahman, Azman Jalar, Norinsan Kamil Othman, Roslina Ismail, Wan Yusmawati Wan Yusoff, Maria Abu Bakar
• Keywords: Gamma, Nanoindentation, Solder, X-Ray Diffraction (XRD)

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