ISSN: 0884-6804
Page Count: 9

The Effect of Biofouling on Graphite/Epoxy Composites
Little, BJ
Stennis Space Center, MS

Puh, JS
Texas A&M University, TX

Wagner, PA
Stennis Space Center, MS

Bradley, WL
Texas A&M University, TX

Abstract

This research program seeks to determine if the presence of marine microorganisms and the biofouling they produce will accelerate the degradation of graphite/epoxy composite materials. Graphite/epoxy samples were conditioned for 4 months in sterilized seawater (no microorganisms), natural seawater (with microorganisms), and air. In addition, half of the tested samples were also subjected to three-point bending while conditioning.

Moisture absorption data was gathered before and after immersion and correlated with tensile and acoustic emission data. Results of tensile tests showed seawater in general had a larger effect on ultimate tensile strength than microorganism effects. However, sample stress state while conditioning had negligible effect on mechanical properties. These results were most likely due to plasticization of the matrix and relief of fabrication residual stresses through moisture absorption and fiber dominated behavior of the specimens. Acoustic emission results showed that the trend for high amplitude hits for each exposure condition was consistent with the tensile test results. However, due to the effects of moisture on three different relaxation mechanisms, the low amplitude hits were not as consistent.

Keywords:
polymeric composites, microbiologically influenced corrosion, biodeterioration, mechanical testing, acoustic emission, microbial, carbon fiber, seawater

Paper ID: CTR10501J
DOI: 10.1520/CTR10501J
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