Processing of Thermoplastic Composite Structures

Gabriel Gumede

Department of Mechanical EngineeringDurban University of Technology

November 2007

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Introduction

• What is Thermoplastic compositeThermoplastic :Deformable, melts to liquid and freezes to brittle glass

state.Recyclable (remelted and remoulded).

Composite :Material made from two or more materials with different physical or chemical properties and remain separate

and distinct within the finished structure.

Thermoplastic composite is a recyclable, reinforced plastic material.

• Polymeric composite application

Automotive, aerospace, marine, civil construction, sports, and many others.

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Problem Statement

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• Nanocomposites

• Vacuum Bagging

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• Autoclaving

Enhances composite bonding and curing.

• Resin Transfer Moulding

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• Thermoforming

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Work already done

• Kunihiko Murayama - orietation control of short fibres in a - liquid matrix by loading a magnetic field. - Nickel coated graphite fibre - ultrasonic vibration

• Liu and Chen developed water-assisted injection moulding technology. Water penetrates into the core of the composite and pushes the material into the mould wall thereby aligning the fibres in the mould direction.

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Manufacturing Processes

• Pultrusion

• Extrusion moulding

• Compression moulding

• Injection moulding

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Pultrusion Process

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Modified Pultrusion/Extrusion Moulding Process

creel

Fibre spreader

Heater rollers

Impregnating toolWith rollers

chiller

Pullers

Winder

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Impregnating Tool Rollers

Tool mouth

Fibre entrance port

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Extrusion moulding

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Principle of a Plasticator

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Compression moulding

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Injection moulding

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Thermoplastic Pellets (TP)

Glass fibres

Process Chart

Modified Pultrusion TP with glass fibres

Heating

Extrusion

Hot pressing

Components

Injection moulding

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Fibre Orientation

• Factors affecting fibre orientation

Moulding processes

Gates, Initial Charge and Part Geometry

Thickness of the moulded part

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Outline of Research

• Develop a technique of aligning glass fibres using extrusion, injection and compression moulding processes.

• Optimise the mechanical properties by controlling the fibre orientation.

• Determine critical fibre length

• Produce complex shaped reinforced thermoplastic composite components.

• Test and analyse reinforced thermoplastic components.

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I would like to thank Kenton for

their support through the Hystou programme