Composites

The following page of notes will cover:

Fibre-based composites
Particle-based composites
Sheet-based composites

Composite: a mixture of two or more materials combined to improve the materials properties (e.g. corrosion resistance)

Fibre-based composites

Carbon fibre:

Advantages	Disadvantages
Lightweight High tensile strength Durable Corrosion resistant Good electrical conductor	Can break/shatter Brittle Relatively expensive

Uses: F1 cars, bicycles, tennis rackets

Glass fibres (GRP):

Advantages	Disadvantages
Good strength to weight ratio Good tensile strength Corrosion resistant Durable	Brittle/can shatter easily Not very heat resistant

Uses: Piping, boat hulls, fighter planes

Particle-based composites

Reinforced concrete:

Advantages	Disadvantages
Good compressive/tensile strength Can be casted in complex shapes Durable/impact resistant Excellent fire resistance	Energy and water intensive Expensive Not environmentally friendly

Uses: F1 cars, bicycles, tennis rackets

Sheet-based composites

Medium density fibreboard:

Advantages	Disadvantages
Cheap Uniform strength Finishes well Comes in any size and thickness	Poor strength Splinters/cracks easily Poor woodworking properties

Uses: Furniture, flooring, storage units

Hardboard:

Advantages	Disadvantages
Stiff Resistant to scratches and moisture Easy ti finish with veneers Durable	Can't be used outside Not waterproof Not as strong as natural timbers

Uses: Furniture components, wall panelling, door skins

Chipboard:

Advantages	Disadvantages
Inexpensive Eco-friendly Strong Can take a variety of finishes	Prone to cracking and splintering Hard to cut Adhesive problems under stress cause splintering

Uses: Packaging, flooring, furniture

Plywood:

Advantages	Disadvantages
High uniform strength (cross-grain) Can be easily finished Less susceptible to moisture damage then MDF Good availability	More expensive then MDF Difficult to cut Splinters easily

Uses: Construction, cabinets, general product making

Topic test:

Composite Questions