An investigation into a magnetic compaction technique for composite manufacturing

Abstract

Fiber reinforced polymer composites are an aerospace and defense material. These materials are widely used in the production of components and parts which require high weight to strength ratios or corrosion resistance. The automotive, aero, marine as well as sporting industries are increasingly requiring components with such characteristics. This has led to an increase in demand in the composite industry. A composite is a material made from a combination of fiber reinforcement and resin. The reinforcement is generally made of Glass, Carbon or Aramid fiber which is woven in a fabric. While resins are typically thermoplastic such as polyester, vinyl ester, phenolic and epoxy. The fiber and resin are combined and compacted together in order to manufacture an item. There are various manufacturing techniques which are utilized to produce fiber reinforced composite components. Many items are manufactured using closed moulding techniques. The process involves the combining of fabric preform with a liquid resin within the mould cavity. After a certain period the component is removed from the mould. The strength, stiffness (mechanical properties) and strength to weight ratio of a composite material are affected by voids (air pockets) and the component’s thickness. Both the air voids and thickness are influenced by compaction during the manufacturing process. Increasing compaction during moulding improves the material properties and ultimately the final product, component or part. This research is aimed at investigating the possibility of utilizing magnetic compaction in fiber reinforced composite manufacturing. The desired technique will be intended to offer improved compaction without requiring any tooling modifications. The proposed technique would fall into the category of the light closed mould compression techniques which utilizes Glass Reinforced Plastic (GRP) tooling. This technique will also attempt to address certain issues experienced in light closed mould techniques. The magnetic compaction technique would be investigated in an effort to offer a scalable technique which has an improved fiber volume fraction and mechanical properties. Currently no closed mould techniques implement magnetic compaction. The research will review the combination of light closed moulding techniques and the working principles of magnetism.