Title: Validation of CFRP Surface Preparation using Water Contact Angle
Authors: Matthew Nichols, Rose Roberts, Giles Dillingham, Sam Newton, Monika Rakoczy
DOI: 10.33599/nasampe/c.24.0270
Abstract: Carbon-fiber reinforced polymers (CFRPs) are an increasingly popular class of materials with applications in several industries, such as structural materials for adhesively bonded vehicles. A central component in achieving reliable adhesive performance is high quality surface preparation prior to bonding. In this study, water contact angle was used to gauge the quality of several different surface preparation methods on unidirectional toughened prepreg CFRP panels. Panels were prepared using manual solvent cleaning followed by manual abrasion of varying intensities, grit blasting, or plasma treatment. An array of one hundred water contact angle measurements were taken across the panel surfaces to map any spatial variation in surface state. Panels were then aged under ambient conditions (~21 °C, 40 % RH) and characterized with water contact angle at different time intervals to track the stability of these treatments. Panels were found to be sensitive to the specific choice of surface preparation materials (e.g. stearated vs non-stearated abrasive paper, fresh vs aged grit blast media) which had a significant effect on surface energy. A select set of preparation methods were chosen for adhesion performance testing. Prepared surfaces were bonded into lap shear and double cantilever beam specimens to compare adhesion performance between the treatment types. These CFRP surfaces were found to be sensitive to changes in surface preparation methodology and aging.
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Conference: CAMX 2024 | San Diego CA
Publication Date: 2024/9/9
SKU: TP24-0000000270
Pages: 16
Price: $32.00
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