A MODEL TO PREDICT THE THROUGH-THICKNESS DISTRIBUTION OF HEAT-GENERATION IN CROSS-PLY CARBON-FIBER COMPOSITES SUBJECTED TO ALTERNATING MAGNETIC-FIELD

A theory of local and global mechanisms of heat generation and distrib ution in carbon-fiber-based composites subjected to an alternating mag netic field has been proposed. A model is developed which predicts the strength and distribution of thermal generation through the thickness of carbon-fiber-based laminated composites. Earlier work established the distribution of point voltages in the plane of the laminate which exist in the form of potential differences between fibers in adjacent plies in a cross-ply or angle-ply laminate system. In the present work , a capacitive layer microstructure is formulated which models the act ual fiber-reinforced-polymer microstructure from a square-packing assu mption to a series of conductive parallel plates. From this capacitive layer analogy, an effective parameter of heating, gamma, is defined w hich establishes the distribution of heating through the thickness. Ex treme gradients in this thermal source can exist with peaks occurring at the interfaces of ply/ply orientation changes. An optimization stud y establishes the effect of various micro- and macrostructural paramet ers on the parameter gamma. Several parametric studies are performed o n a computer algorithm which calculates gamma to further analyze these effects.