Using Microwave-Assisted Powder Metallurgy Route and Nano-size Reinforcements to Develop High-Strength Solder Composites


In the present study, Sn-0.7Cu and Sn-3.5Ag lead-free solders used in the electronics packaging industry were reinforced with different volume percentages of nano-size alumina and tin oxide particulates, respectively, to synthesize two new sets of nanocomposites. These composites were developed using microwave-assisted powder metallurgy route followed by extrusion. The effects of addition of particulates on the physical, microstructural, and mechanical properties of the nanocomposites were investigated. Mechanical properties (microhardness, 0.2% YS, and UTS) for both composite systems increase with the presence of particulates. The best tensile strength was realized for composite solders reinforced with 1.5 vol.% alumina and 0.7 vol.% tin oxide particulates, which far exceeds the strength of eutectic Sn-Pb solder. The morphology of pores was observed to be one of the most dominating factors affecting the strength of materials.

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The authors acknowledge the support received for this research work ref: C-534-000-003-414 from the Minerals, Metals and Materials Technology Centre (M3TC) of the National University of Singapore.

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Nai, S.M.L., Kuma, J.V.M., Alam, M.E. et al. Using Microwave-Assisted Powder Metallurgy Route and Nano-size Reinforcements to Develop High-Strength Solder Composites. J. of Materi Eng and Perform 19, 335–341 (2010).

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  • lead-free solder
  • metal-matrix nanocomposite
  • microwave sintering
  • tensile properties