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

Abstract

The invention provides a tin-plated copper-alloy material for terminal and a method for producing the same with an excellent insertion / extraction performance and has an object of reducing dynamic friction coefficient to 0.3 or less with an excellent electrical-connection characteristic. A Cusn alloy layer / a NiSn alloy layer / a Ni or Ni alloy layer are formed between a Sn-based surface layer and a substrate made of Cu or Cu alloy; the Cusn alloy layer is a compound-alloy layer containing Cu 6 Sn 5 as a major proportion and a part of Cu in the Cu 6 Sn 5 is displaced by Ni; the Nisn alloy layer is a compound-alloy layer containing Ni 3 Sn 4 as a major proportion and a part of Ni in the Ni 3 Sn 4 is displaced by Cu; an average interval S of point peaks of the Cusn alloy layer is not less than 0.8 [mu]m and not more than 2.0 [mu]m; an average thickness of the Sn-based surface layer is not less than 0.2 [mu]m and not more than 0.6 [mu]m; an exposed-area rate of the CuSn alloy layer exposed at a surface of the Sn-based surface layer is not less than 1% and not more than 40%; an average of equivalent-circle diameter of the exposed portions of the Cusn alloy layer exposed at the surface of the Sn-based surface layer is not less than 0.1 [mu]m and not more than 1.5 [mu]m; and dynamic friction coefficient is not more than 0.3.

Description

technical field [0001] The present invention relates to a tin-plated copper alloy terminal material useful as a terminal for a connector, especially a terminal for a multi-pin connector, used for connecting electrical wiring of automobiles or consumer equipment, and a method for producing the same. [0002] This application claims priority based on Japanese Patent Application No. 2012-148575 for which it applied in Japan on July 2, 2012, and uses the content here. Background technique [0003] Tin-plated copper alloy terminal material is a terminal material in which a CuSn alloy layer is formed on the lower layer of the Sn-based surface layer on the surface layer after performing copper plating and tin plating on the base material made of copper alloy, and is widely used. For terminal material. [0004] In recent years, for example, as electrification of automobiles has been rapidly advanced, the number of circuits of electrical equipment has increased, and therefore the si...

AI Technical Summary

Problems solved by technology

However, when the CuSn alloy layer is exposed on the surface layer, Cu oxides are formed on the surface layer, resulting in an increase in contact resistance and a decrease in solder wettability.

In addition, there is a problem that even if the average roughness of the CuSn alloy layer is controlled, the dynamic friction coefficient cannot be reduced to 0.3 or less.

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