Functionalised Graded Composites for Induction Processing in Manufacture

Abstract

This project focuses on investigating several methods, such as magnetic positioning and liquid resin printing, to introduce and position carbon nanotubes (CNTs) in a viscous medium. The combination of magnetic manipulation through static magnetic field and liquid resin printing represents an unprecedented approach that could be used in composite manufacture, specifically for patch repair applications of composite materials. The possibility of spatially positioning the CNTs in a tailored and accurately controlled fashion is a focal point of the presented project. The main advantages of the proposed approach are the local CNT positioning and heat dissipation tailoring by conductive networks within the part. More precisely, the generation of such conductive pathways through spatial additive positioning can be used to trigger inductive heating by alternated magnetic field. Homogeneous heat distribution within the inductively sensitive region could be aided by an inhomogeneous magnetic field.
CNTs were metal functionalised through chemistry-based electroless plating. Metal-plated CNT positioning through static magnetic field was achieved both in epoxy resin and within glass fabric. The CNT positioning within fabric was assessed by introducing the CNTs within fabric through liquid resin printing. The CNT positioning was characterised within fabric by elemental analysis of selected fracture surfaces across the patch by assessing the metal particle distribution. Metal-plated CNTs affected the preform resin cure kinetics. The effect of grading the electrical conductivity within the patch by spatially locating the nanotubes was assessed through numerical inductive modelling. Homogeneous spatial distribution of CNTs provided uniform heat dissipation within the patch by means of eddy current generation. Enhancement of dielectric properties of the resin matrix by synergetic effect of dielectric particles and CNTs can be combined with eddy currents to aid and better control the cure process. Further experimental work on inductive heating for patch repair represents the next step of this investigation.

Date of Award	19 Mar 2019
Original language	English
Awarding Institution	University of Bristol
Supervisor	Ian Hamerton (Supervisor), Dmitry Ivanov (Supervisor) & Bhrami Jegatheeswaram Pillai (Supervisor)