Tin-plated copper-alloy material for terminal and method for producing the same

摘要

Tin-plated copper-alloy material for terminal having: a substrate made of Cu or Cu alloy; an Sn-based surface layer formed on a surface of the substrate; and a Cu-Ni-Sn alloy layer including Ni formed between the Sn-based surface layer and the substrate, in which the Cu-Ni-Sn alloy layer is made of: fine Cu-Ni-Sn alloy particles ; and coarse Cu-Ni-Sn alloy particles, an average thickness of the Sn-based surface layer is not less than 0.2 µm and not more than 0.6 µm, an area ratio of the Cu-Ni-Sn alloy layer exposed at a surface of the Sn-based surface layer is not less than 10% and not more than 40%, and a coefficient of kinetic friction of the tin-plated copper-alloy material for terminal is not more than 0.3.