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Salt Water Exposure Effects on Single-Layer, Unidirectional Carbon-Fiber Reinforced Polymer Circuit Analog Absorbers

By Joseph C. O'Donnell and Ram M. Narayanan
Progress In Electromagnetics Research B, Vol. 93, 47-65, 2021


This paper explores the effects of extended exposure to salt water fog on the microwave absorption properties of unidirectional carbon-fiber reinforced polymer (CFRP) circuit analog absorbers (CAA). Single-layer CFRP CAAs were fabricated using a wet-layup technique and were then subjected to a controlled salt water fog chamber following B117 standards. A total of ten samples using 305 g/m2 areal-weight unidirectional CFRP were fabricated. Three samples were withdrawn from the salt water environment at ten-day intervals and tested, with the final samples being withdrawn after 30 days. The mass of each sample was measured immediately after removal to measure mass-accumulation and after a five-day interval to measure mass-loss. A free-space microwave reflection measurement system was implemented to track and quantify changes to the absorption capabilities of the CAA. A physically-based electromagnetic model was developed to characterize the changes caused by salt water absorption, and good agreement was observed with measured data.


Joseph C. O'Donnell and Ram M. Narayanan, "Salt Water Exposure Effects on Single-Layer, Unidirectional Carbon-Fiber Reinforced Polymer Circuit Analog Absorbers," Progress In Electromagnetics Research B, Vol. 93, 47-65, 2021.


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