Conductive material for connecting part and method for manufacturing the conductive material

Abstract

In a conductive material, on the surface of a base material composed of a Cu plate strip, a Cu-Sn alloy covering layer, which contains a Cu of 20-70at% and has an average thickness of 0.1-3.0[mu]m, and an Sn covering layer having an average thickness of 0.2-5.0[mu]m are formed in this order, and a part of the Cu-Sn alloy covering layer is exposed from the surface of the Sn covering layer at an exposing area rate of 3-75%. Reflow process is performed to the material surface, and preferably, the arithmetic average roughness Ra at least in one direction is 0.15[mu]m or more, the arithmetic average roughness Ra in all the directions is 3.0[mu]m or less, and the average thickness of the Cu-Sn alloy covering layer is 0.2[mu]m or more. The conductive material is manufactured by forming an Ni plating layer, and further, a Cu plating layer and an Sn plating layer as needed on the roughened base material surface, then by performing reflow process.

Description

technical field [0001] The present invention relates to a conductive material for connector terminals and connecting parts such as bus bars mainly used in electrical wiring of automobiles and household appliances, and particularly relates to the improvement of the friction resistance when plugging and unplugging male terminals and female terminals. It is a conductive material for fitting-type connecting parts that can reduce wear and tear, and provide electrical connection reliability during use. Background technique [0002] Among the conductive materials for connecting parts such as connector terminals and busbars used in the connection of electrical wiring of automobiles and civil equipment, in addition to requiring low-level signal voltage and current, high reliability of electrical connection is important. Except for the case of a circuit, etc., Cu or Cu alloy with Sn plating (including Sn alloy plating such as solder plating) is used. Compared with Sn plating, Au plat...

AI Technical Summary

Problems solved by technology

In addition, the insertion force of the terminal with the Cu-Sn alloy layer formed on the surface is further reduced

On the other hand, if the thickness of the Sn layer is reduced, there is a problem that the contact resistance of the terminal increases when it is kept for a long time in a high-temperature atmosphere as high as 150°C such as an engine room of a motor vehicle.

In addition, when the thickness of the Sn layer is thin, the corrosion resistance and solderability are also reduced.

In addition, the Sn layer is also prone to micro-sliding wear

In this way, in this type of terminal, the low insertion force cannot be sufficiently obtained, and after repeated plugging and unplugging, after being kept in a high-temperature atmosphere for a long time, in a corrosive environment or in a vibration environment, it can still maintain low contact resistance and other fittings. The characteristics required by the type terminal, so further improvement is required

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