| Budget Amount *help |
¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000)
Fiscal Year 2015: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
Fiscal Year 2014: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000)
Fiscal Year 2013: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000)
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| Outline of Final Research Achievements |
Various novel multilayered Sn/Ag3Sn(/Ag) films with Ag thickness of 20-300 nm, which are considered as promising low-cost coating materials for substitution to the noble Au and Ag plating materials, were fabricated by electroplating thin Ag films on reflowed Sn layers on Cu alloy plates toward next-generation high reliable coating materials for automotive connectors and LED lead-frames. The Sn/Ag-based films exhibited excellent thermal stability of electrical contact resistance and reflectance, improved fretting corrosion resistance, and satisfied sulfidizing resistance, superior to conventional Ag and Sn electroplating films. The enhanced performances mentioned above can be mainly attributed to (i) the chemically stable Ag3Sn layer with high hardness that endows a high electrical connection and a low friction coefficient, and (ii) a protective thin SnO film on the intermetallic Ag3Sn layer that isolates the corrosive circumstance.
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