Title: Impact of Core Surface Finish on Adhesion to Face Sheets

Authors: Kian Mohtadi, Michael Standiford, Nicole Larson

DOI: 10.33599/nasampe/s.22.0695

Abstract: During the machining of Kevlar® based honeycomb core composite materials, a common surface defect known as fiber fuzz occurs when the fibers of the cell wall are not cleanly sheared off. Sectors such as the aerospace industry require their composite honeycomb core laminates to perform at the upper end of design loads. Therefore, internal specifications call out for there to be little to no fiber fuzz present on the surface of the core. Solutions to remove fiber fuzz are costly, with common methods involving manually removing fiber fuzz with secondary processing operations. Currently, the extent to which surface finish of the core impacts the adhesion properties with the face sheets is debated within the aerospace industry. To investigate this issue, Hexcel partnered with Western Washington University (WWU) to investigate the impacts of fiber fuzz on adhesion strength of face sheets bonded to Kevlar® honeycomb core. The investigation that proceeded required the development of a measurement system using ImageJ to quantify the degree of fiber fuzz on the surface of machined Kevlar® honeycomb cores. Test coupons were manufactured using industry methods and were characterized for their adhesion strength following ASTM D1718, Standard Test Method for Climbing Drum Peel for Adhesives.

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Conference: SAMPE 2022

Publication Date: 2022/05/23

SKU: TP22-0000000695

Pages: 16

Price: $32.00