Original paper(Vol.48 No.5 pp.429)

Evaluation of Damage Behaviors on Woven Cloth Fabric Reinforced Composites by In-Situ SEM Observation
-Effect of Surface Treatment-

Nishiyabu Kazuaki; Yokoyama Atsushi; Zako Masaru

Abstract:The effect of interfacial properties on damage behaviors of woven cloth fabric reinforced composites has been investigated by the edge cross sectional observation of laminate under the tensile load in SEM. Test specimen used is vinyl ester resin matrix laminated composite reinforced by glass woven cloth. It is obvious that the surface treatment conditions of the fiber have affected the appearance of microscopic damages, such as the interfacial debonding and matrix cracking into the fiber bundle, or the generation of AE event. In the case of the fiber treated with the silane coupling agent suitable for the matrix resin, only a few cracks occur into the fiber bundle just prior to the maximum load, and AE events generate fewer. In the case of chemical mismatch treated fiber or non treated fiber, however, much more cracks occur into the fiber bundle at the lower tensile load, but the generation behavior of AE events differs with each other. It is found by in situ SEM observation that the fiber surface treatments have affected the initiation and progression of microscopic damage under the tensile load. Thus, it can be concluded that in situ SEM observation with measuring both tensile load and AE event count is a useful evaluation method for understanding the effect of interfacial property on microscopic damage behavior.

Key Words:in-situ SEM observation, woven laminated composite, surface treatment, tensile test, damage behavior