Abstract
The commercial market of Sn–Pb solder is gradually decreasing due to its toxicity, calling for Pb-free substitute materials. Sn–Ag alloy is a potential candidate in terms of good mechanical property. The major problematic issue of using Sn–Ag is their high melting temperature, consequently this study is dedicated to lowering the melting temperature of Sn3.5Ag (wt%) alloy by develo** nanomaterials using a chemical reduction approach. The resultant nanocrystalline Sn3.5Ag is characterized by field emission scanning electron microscope. The size dependence of the melting temperature is discussed based on differential scanning calorimetry results. We have reduced the melting temperature to 209.8 °C in the nanocrystalline Sn3.5Ag of (32.4 ± 8.0) nm, compared to ~221 °C of the bulk alloy. The results are consistent with the prediction made by a relevant theoretical model, and it is possible to further lower the melting temperature using the chemical reduction approach developed by this study.
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Acknowledgments
This work was supported by the National Natural Science Foundation of China (50971086, 51171105).
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Zhao, B., Zhang, W., Zou, C. et al. Low melting point nanocrystalline Sn–Ag solder synthesized by a refined chemical reduction method. Chin. Sci. Bull. 59, 4147–4151 (2014). https://doi.org/10.1007/s11434-014-0528-7
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DOI: https://doi.org/10.1007/s11434-014-0528-7