Most connectors are made from copper or copper alloys, with beryllium copper and phosphor bronze being the most common base materials due to their high electrical conductivity, low stress relaxation, and competitive cost. The most significant drawback is copper’s low resistance to corrosion, which can lead to electrical failure of connectors. For this reason, a layer of gold is often plated on the surfaces of connectors to seal off the base metal from being directly exposed to the environment. As an economical practice, gold flashing has been used to protect electrical contacts from corrosion. However, there is increasing evidence indicating that gold flashing can be detrimental in applications calling for long-term reliability. This paper provides insight into reliability issues of gold flash.

Issue Section:
Technical Papers
Keywords:
gold, corrosion protection, reliability, electrical contacts, corrosion resistance, electric connectors
Topics:
Corrosion, Reliability, Porosity, Diffusion (Physics), Corrosion resistance
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