| 摘要 |
PROBLEM TO BE SOLVED: To provide a tinned copper alloy sheet for fit type terminals that has a small coefficient of friction and a small change of contact resistance with the lapse of time. SOLUTION: An optional Ni covering layer, a Cu-Sn alloy covering layer and a surface plating layer comprising an Sn covering layer are formed in this order on a copper or copper alloy sheet and graphite particles are dispersedly attached onto the Sn covering layer. The Ni covering layer has an average thickness of 0.1-1.0 μm, the Cu-Sn alloy covering layer has an average thickness of 0.1-1.0 μm and the Sn covering layer has an average thickness of 0.1-2.5 μm. The graphite particles cover the surface of the Sn covering layer in an area ratio of 3-30%, and among the graphite particles, graphite particles whose particle diameter is ≥2 μm have an average particle diameter of 3-30 μm and graphite particles whose particle diameter is ≥10 μm occupy ≥3% by number. Optional Ni plating, Cu plating and Sn plating are carried out on a copper or copper alloy sheet, graphite particles are attached to the surface and reflow treatment is carried out to manufacture the objective tinned copper alloy sheet material. COPYRIGHT: (C)2011,JPO&INPIT |
