Abstract:

Corrosion-induced contact degradation at gasket joints has been found to be a primary mechanism of electromagnetic shielding degradation and ultimate shielding failures of zinc-coated steel enclosures. The shielding degradation takes place over an extended period of time and causes increased vulnerability of enclosed electronics to external radiations that compromise its security and functionality. In this study, the environmental factors are investigated against the operational factors, and the results indicate that, even in the electromagnetic shielding applications in which the presence of electrical current flowing across the shielding assembly is considered as well a factor of corrosion, the environmental condition remains the dominant one. The results also indicate that availability of electrolyte in a corrosion process of zinc-coated steel is a root cause of different corrosion products and duration of time to failure, and the commonly seen dark and black corrosion deposits at gasket joints is a result of a low level of electrolyte availability in a typical in-door environment of shielding applications.

Keywords: Zinc-coated steel enclosure, electromagnetic shielding, gasket joint, beryllium-copper fingerstock, corrosion, shielding degradation

Complete article is available to CALCE Consortium Members.