ISSN: 0884-6804
CODEN: JCTRER
Page Count: 5

Analysis of Neat Resin Cracking Induced by Rapid Moisture Loss
Adams, DF
Graduate student and professor of mechanical engineering, Composite Materials Research Group, University of Wyoming, WY

Mahishi, JM
Graduate student and professor of mechanical engineering, Composite Materials Research Group, University of Wyoming, WY

Abstract

During routine moisture conditioning of neat (unreinforced) resin test specimens of two different types of epoxy polymers, the active humidity control of the chamber failed, causing a rapid drop in the humidity level. Approximately half of the specimens of one material cracked while none of the specimens of the other material were damaged. The accident was later recreated, monitoring the cracking as a function of time using acoustic emission sensors mounted on individual specimens, while also recording the relative humidity decrease as a function of time. An analytical study was also performed, using a finite-element finite-difference technique to predict the moisture gradients in the specimens and a finite-element analysis to predict the initiation and propagation of cracking as a function of time. The results presented here demonstrate the ability to predict cracking and indicate the material parameters that dominate the process.

Keywords:
composites, epoxy resins, crack propagation, neat resin, epoxy matrix, moisture effects, acoustic emission, finite-element analysis

Paper ID: CTR10837J
DOI: 10.1520/CTR10837J
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