TIN-PLATED COPPER-ALLOY TERMINAL MATERIAL

摘要

By forming a nickel-based coating layer or a cobalt-based coating layer having a coating thickness of 0.005 μm or larger and 0.05 μm or smaller on an outermost surface of a tin-based surface layer of a terminal material of low-insertion force in which an asperity shape of an interface between a copper-tin alloy layer and a tin-based surface layer is controlled, it is possible to reduce insertion force of fitting even though all-purpose tin-plated terminal material is used by combination.

主权项

1. A tin-plated copper-alloy terminal material comprising:
a base material which is made of copper or copper alloy; a tin-based surface layer which is formed on a surface of the base material and has an average thickness of 0.2 μm or larger and 0.6 μm or smaller; a nickel-based coating layer or a cobalt-based coating layer which is formed on an outermost surface of the tin-based surface layer and has a coating thickness of 0.005 μm or larger and 0.05 μm or smaller; and a copper-tin alloy layer/a nickel-tin alloy layer/a nickel layer or a nickel-alloy layer which are formed between the tin-based surface layer and the base material in order from the tin-based surface layer, wherein the copper-tin alloy layer is a compound-alloy layer in which a major ingredient is Cu6Sn5 and a part of copper of Cu6Sn5 is substituted by nickel; the nickel-tin alloy layer is a compound-alloy layer in which a major ingredient is Ni3Sn4 and a part of nickel of Ni3Sn4 is substituted by copper; an average gap “S” of point peaks of the copper-tin alloy layer is 0.8 μm or larger and 2.0 μm or smaller; and a dynamic friction coefficient at a surface of the tin-plated copper-alloy terminal material is 0.3 or lower.