Composites

Learning Intention:Show an understanding of the term composite

Be aware of practical applications of some composites

Composites

A composite material is produced when two or more materials are combined.

This gives us a material with improved properties

GRP (glass reinforced plastic)

GRP consists of strands of glass fibres that have been coated in polyester resin

GRP (glass reinforced plastic)

https://www.youtube.com/watch?v=DuA4OM1kzeY

GRP (glass reinforced plastic)

The polyester resin enables the GRP to be moulded into shape and bonds the fibres togetherThe resin improves the strength and toughnessIt is waterproofIt can be any colour (pigment is added)Good thermal and electrical insulatorGood resistance to chemicals

Carbon fibre reinforced plastic

Strands of carbon that have been coated in polyester resin

The carbon fibre is woven into matting and the polyester resin bonds it together enabling the matting to be moulded

Carbon fibre reinforced plastic

https://www.youtube.com/watch?v=q0mQk1s4tKo

It has all the properties of GRP but is even stronger, tougher and lighter

40% lighter than aluminium 60% lighter than steel

Kevlar

Similar to carbon fibre matting. It consists of strands of a very strong plastic that is woven to form a mattThe woven matt acts like a very strong net that can stop a knife and even a bullet

Kevlar

Examiner’s Tip• You need to be able to identify a range of composite materials• You must be able to name specific composite materials

• You must understand the properties of a range of composite materials

Check your understandingWhat is a composite?

A composite material is produced when two or more materials are combined.

This gives us a material with improved properties

Check your understandingWhat’s the composite?

What are its properties? Give some usesWaterproof, good resistance to chemicals, good thermal and electrical insulator, tough and strong

Check your understandingWhat’s the composite?

What are its properties? Give some usesStrong, tough and lightweight. Woven matting acts as a net. With added plastic resin can be moulded

Check your understandingWhat’s the composite?

What are its properties? Give some usesLightweight, tough and strong. Can be moulded

Check your understandingPut these 3 composites in order of weight, strength and toughness

Task

Research into other composite materials. They are more common than you think. You are sitting very near a composite material as you read this!Find images, and of those covered in today’s lesson. Add them to your notebook – with notes