This research is to develop both experimental and analytical methods to determine internal stresses induced in laminated composite structures during processing. Through these internal stress characterizations, a methodology will be developed that can provide a basic understanding for controlled processing and performance of composites. Both thermosetting and thermoplastic polymer matrices reinforced with continuous fibers, that are potential candidates for structural materials in the electric power industry, will be examined using well established as well as novel lamination processes. As an integral part of this study, several process monitoring techniques will be evaluated; these techniques could also be used for on-line, long term durability monitoring. Internal stress analysis will be studied on macroscopic as well as microscopic (micro-mechanical) scale considering both time dependent (kinetic) and time independent (thermodynamic) effects. Through the experimental and analytical approach, an attempt will be made to characterize composite system molecular and morphological structural features that are influenced and/or give rise to the internal stresses developed during processing, leading to full property characterization. It is anticipated that the results derived from this study, in conjunction with previous developments, will provide a basic methodology for process analysis of laminated composites that may also provide fundamental information in screening new materials and processes for load bearing structural application of composites in real manufacturing operations focused on the needs of the electric power industry.
