Microwave Curing of Composites

Abstract

A model was developed which describes the microwave curing process of continuous fiber reinforced organic matrix composites. On the basis of the model, a computer code was developed which provides the temperature distribution, the resin viscosity, the degree of cure of the resin, and the resin contents of the composite and the bleeder during microwave curing of flat plate composites. In addition, the computer code gives the void sizes and the residual stresses after the cure. Tests were conducted using a microwave oven measuring the temperature distribution inside Fiberite S2/9134B glass epoxy composites, and the temperature distribution inside and resin flow out of Hercules AS/3501-6 graphite epoxy composites. The data were compared with results calculated with the computer code for the conditions employed in the tests, and good agreements were found between the data and the numerical results. Parametric studies were also performed to illustrate how the model and associated computer code can be used to determine the appropriate microwave cure cycle which results in a composite that is cured uniformly and in the shortest amount of time.