Abstract

For polymer composite product manufacture, curing is the most critical step in achieving desired mechanical
properties. Conventional cure processes involve thermal curing in ovens and autoclaves where the process is
time and energy intensive. Microwave assisted curing is one of the proven methods of curing polymer composites
that could lead to substantial reduction in cure cycle time, energy requirements, and operational costs due to its
instantaneous, volumetric mode of heating. Our results on microwave processing of aerospace grade glass-epoxy
composites have shown that the process time saved is ~90% and energy saved is ~60% vis-à-vis a conventional
thermal curing process. In addition, the cure uniformity, thermal and mechanical properties achieved by
microwave processing are comparable/superior. Thus, an alternative cure approach has been developed at CSIR-
NAL for the first time in India, which has better techno-economic significance for aerospace composites. The
efficacy, scalability, and versatility of molecular weight assisted curing have been realized from chemistry to
component level through our unique microwave cure facility and comprehensive studies therein. This article is
mainly centered on the challenges and successes of microwave assisted processing of composites for structural
applications. Proposed futuristic directions are also outlined.