Title: Effect of Surface Contamination with Mitigation Methods on Adhesive Composite Bond Integrity and Durability

Authors: Brian Hernandez, Gabriela Gutierrez-Duran, Juliette Dubon, Mauricio Pajon, Jose F. Rojas-Sanchez, Benjamin Boesl, and Dwayne McDaniel

DOI: 10.33599/nasampe/s.19.1481

Abstract: Adhesive bonds offer multiple advantages over traditional fasteners such as reduced weight and a potential decrease of stress concentrations due to hole fabrication. However, the influence of undesirable bonding conditions on the strength of adhesive bonds such as bonding surface contamination has not been reliably characterized. In this study, a method was proposed to create a scalable weak bond using a continuous spray approach. In this approach, the mass of a silicon based mold release can be scaled to achieve various levels of contaminant effect. Methods to mitigate the effect of contamination such as sanding and solvent wiping were investigated, and repeated using environmental exposure to investigate bond durability. To assess bond strength, Dual Cantilever Beam (DCB) tests were performed and the critical energy release rate was measured. Results showed the critical energy release rate of the bonded joints correlated well with the mass of the contaminant applied to the surface. Results of the mitigation procedures showed that solvent wipes led to minimal statistical changes. However, a combination of wipe-sand-wipe procedure yielded a partially recovered load capacity and failure mode. Environmental exposure testing revealed no added combinatory effect with the addition of the contaminate on the surface.

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Conference: SAMPE 2019 - Charlotte, NC

Publication Date: 2019/05/20

SKU: TP19--1481

Pages: 12

Price: FREE