Honeycomb Core and the Myths of Moisture Ingression

• Published in: Applied composite materials Vol. 17; no. 3; pp. 293 - 307
• Main Author: Fogarty, John H.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.06.2010; Springer Nature B.V
• Subjects: Carbon; Carbon-epoxy composites; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Gain; Honeycomb; Honeycomb construction; Honeycomb cores; Industrial Chemistry/Chemical Engineering; Materials Science; Moisture; Polymer Sciences; Thermal cycling; Environmental exposure; Composites; Honeycomb; Water trapping; Sandwich structures; Moisture ingression
• ISSN: 0929-189X; 1573-4897
• DOI: 10.1007/s10443-009-9121-7

While it is true that honeycomb core can trap moisture, it is a myth that widespread moisture ingression is an inevitable outcome when honeycomb sandwich structures are exposed to real world environments. It is also a myth that when moisture ingression occurs, progressive weight gain and strength loss are inevitable outcomes. Using a rebuttal of a 2004 honeycomb-critical paper as the focal point, this paper summarizes multiple sources which indicate both that moisture ingression is preventable and, even if it does occur, that proper material choices can prevent severe consequences. These claims are further supported by results from in-plane compression testing of typical (0.064 g/cm 3 aramid-paper/phenolic core with 0.116 cm carbon/epoxy faces) composite honeycomb sandwich specimens after impacting, water submersion, and extensive thermal cycling.