Cure monitoring of carbon/epoxy composites using dielectrometry technique.

摘要

The performance of carbon/epoxy composite materials largely depend on cure history, hence there is a perceived need to improve the process of curing. The goal is to investigate the feasibility of incorporating the existing dielectric cure monitoring system, which can monitor cure, using dielectrometer, and record, in real time, the degree of cure of a composite part during its curing process in the current production autoclave or oven. Traditionally, differential scanning calorimeter (DSC), based on heat generation, during the cure process of resin systems with exothermic reaction, is used to determine the degree of cure. The relationship between the DSC and the dielectrometer reading will provide a convenient method of in situ cure monitoring for research, product development and process modeling. Therefore, a relationship is to be established between the dielectric properties from dielectrometer and (a) the degree of cure (alpha) from DSC, (b) glass transition temperature ( Tg) from dynamic mechanical analyzer (DMA) and, (c) mechanical properties in tension, compression and shear to investigate how well the measured dielectric properties reflect the physical, thermal and mechanical properties of the composite for three different cure profiles. (Abstract shortened by UMI.)