Summary: | 碩士 === 國立臺北科技大學 === 資源工程研究所 === 106 === Copper-zinc alloy is the most important material in terms of electronic connectors. Most of the connector industries apply a protective layer by electroplating on the surface of alloy material. Traditional protective layer consists of nickel-plating on the first layer and tin-plating on the surface layer. This research puts major emphasis on multi-layered plating of the alloy material. Design of protective layer is copper-plating on the first layer, nickel-plating on the second layer, and tin-plating on the appearance. Under the requirement of the steady production quantity and maintaining the same operating time of the process and output voltage of the electroplated metal, first of all, we conducted the electroplating process with an additional copper electroplating procedure in the continuous electroplating process. Second, after finishing the electroplating, we observe the crystal structure of the surface of electroplated material by the electron microscope. Finally, we tested the corrosion resistance of multi-layered plating process with salt spray test.
The proposed experimental procedure is as follows. First of all, on a basis of the fixed electroplating time and fixed output voltage of the electroplated metal, we apply electroplating by an additional copper electroplating procedure of the continuous electroplating process. Second, under the requirement of electroplating on the alloy material with the same total film thickness following the original specification, we do not change the film thickness on the surface tin-plating layer, but decrease the film thickness of nickel-plating layer of the original alloy material and add a first copper-plating layer of the original alloy. It is able to achieve the same total thickness as the original double-layered plating does. Finally, we observe the multi-layered and double-layered plated samples after they are under salt spray trial. The analysis indicates that multi-layered plating performs better than double-layered in terms of the corrosion resistance.
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