Curing of Composites Using Internal Resistive Heating

Curing of fiber-resin mixtures is often the critical and productivity controlling step in the fabrication of thermosetting-matrix composites. The long processing times (and costs) have remained the fundamental impediment to widespread commercialization of composites. Shortening the cure cycle time, while ensuring a complete and uniform cure in the product, is imperative for realizing the goal of affordable materials processing, and forms the focus of this investigation. Toward addressing the affordability challenge, this paper explores the use of conductive carbon mats embedded inside the composite as a means of providing internal volumetric resistance heating during the cure process. The supplemental heating results in temperature and cure uniformity through the cross section, as well as speeds up the cure process. In the context of application to resin transfer molding, systematic experimental and theoretical studies on various resistive heating configurations are presented. Optimum processing strategies are derived based on the cure time and microstructural product quality considerations. [S1087-1357(00)01101-1]