Demonstrating inductive heating for energy efficient processing of carbon fibre composites

Abstract

Carbon fibre composite manufacturing is an ever-growing field both within research and industrial applications. The high strength to weight ratio and anisotropic properties of carbon fibre composites allow for intelligent design and potential weight reductions in manufactured parts. With increasing interest in sustainability from industry and wider society, conventional manufacturing processes, such as autoclaves, ovens, and hot press systems, must be challenged as they can often be excessively time consuming and inefficient. This is largely due to the heat transfer mechanism used to initiate thermal curing. Autoclaves and ovens rely on air convection which wastes energy as heat losses to surrounding air, bagging consumables and tooling with high thermal mass. This is not only inefficient but also requires longer and more conservative curing cycles to ensure a part is fully cured, thus reducing rates of production.
Electromagnetic induction has great potential for energy efficient manufacturing of polymer composites. Carbon fibres are electrically conductive and can be directly heated inductively, achieving rapid, localised, and volumetric heating. Heating by electromagnetic induction is not a new field but its application in composites comes with challenges due
to their inherent anisotropic properties. The main obstacle to wider adoption of induction within composites processing is the non-uniformity of temperature distribution in-plane and through the thickness of composite laminates. In this thesis, conductive material enhancement and design of a novel cellular coil architecture are proposed as solutions to the issue of poor temperature
homogeneity. To fully understand the physical heating effects, a finite element model has been developed to predict the heating behaviour of carbon fibre composites with susceptors and various coil geometries. Solutions have been discussed in their efficacy and practicality allowing energy efficiency advantages to be demonstrated as they are key in explaining the need for inductive heating within composites processing.

Date of Award	30 Sept 2025
Original language	English
Awarding Institution	University of Bristol
Supervisor	Dmitry Ivanov (Supervisor), Laura Rhian Pickard (Supervisor) & Ian Hamerton (Supervisor)