volume | PIER Journals

Abstract

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 Three samples were withdrawn from the salt water environment at ten-day intervals and tested, with the final samples being withdrawn after 30 days.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.

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Dr. Joseph C. O'Donnell

Prof. Ram M. Narayanan