Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (23권3호 173-182)

전기접점 재료상에 입힌 경질금고금층의 특성연구 Properties of a Hard Gold plating Layer on Electrical Contace Materials

전기접점 재료상에 입힌 경질금고금층의 특성연구 Properties of a Hard Gold plating Layer on Electrical Contace Materials

최송천;장현구;
;;

성균관대학교 공과대학 금속공학과;성균관대학교 공과대학 재료공학과;
성균관대학교 공과대학 금속공학과;성균관대학교 공과대학 재료공학과;

Abstract

In order to prevent the thermal and enviromenatal degradation of contact materials a nickel layer was plated as an undercoat of gold plating on the surface phosphorous bronze. The thickness of nikel and gold coating and chemical resistance of the coatings were measured at various conditions. Variation of morphology and chemical composition was studied by SEM, EDS and ESCA, respectively. Nickel layer was found to act as a thermal diffusion barrier and to retard the diffusion of copper from substrate to gold coating in the temperature $200^{circ}C$~$400^{circ}C$. below $200^{circ}C$gold coated contacts showed a stable and low contanct resistance, while above $200^{circ}C$ rapid diffusion of copper formed copper oxide on the surface layer and raised the contact resistance. With the nickel thinkness of abount 5$mu$m as an undercoat the gold thinkness of $0.5mu$m, showed satistactory (less than 1 m$Omega$) contact resistance below 20$0^{circ}C$ and corresponding gold thinkness increased to 1.0 m at $300^{circ}C$~$400^{circ}C$.

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