Composite Materials

Question 1

What is a composite material?

Answer 1

A composite material is a mixture of two or more different materials that enhance each others properties.

Question 2

What are the 3 main groups of composite materials?

Answer 2

• Fibre-reinforced composites
• Particle-based composites
• Sheet-based composites

Question 3

Name some Fibre-reinforced composites

Answer 3

• Natural woods
• Polymer mixed with fibres
• GRP
• Plastic laminates
• Carbon fibre

Question 4

Name some Particle-based composites

Answer 4

• Cermets
• Tungsten carbide
• Concretes
• Tarmac

Question 5

Name some Sheet-based composites

Answer 5

• Plywood
• Blockboards
• Chipboard
• Sterling board
• MDF

Question 6

Name some Man-made boards

Answer 6

• Plywood
• MDF
• Chipboard
• Block board

Question 7

What are the common uses of Plywood?

Answer 7

Backs of furniture e.g. cabinets, bottom of draws.

Question 8

What are the common uses of Block board?

Answer 8

Table tops.

Question 9

What are the common uses of Sterling board?

Answer 9

Flooring for sheds and workshops.

Question 10

What are the common uses of Chip board?

Answer 10

Knockdown furniture, kitchen cupboards.

Question 11

What are the common uses of MDF?

Answer 11

Furniture sides.

Question 12

What are the common uses of Hardboard?

Answer 12

Backs of cupboards and drawer bottoms.

Question 13

What is Kevlar a mixture of?

Answer 13

Aromatic and aramid molecules.

Question 14

How does Kevlar work?

Answer 14

Kevlar fibers are woven into a cloth which can be fashioned into protective equipment, it acts like a net which absorbs all the force.

Question 15

Name some uses of Kevlar.

Answer 15

• Body protection
• Sports equipment like skis and helmets
• Sails for wind surfing

Question 16

What are the properties of Kevlar?

Answer 16

• High strength to weight ratio
• Low electrical conductivity.
• High chemical resistance
• High toughness
• High cut resistance
• Flame resistance

Question 17

Name 3 typical fibre-reinforced composites

Answer 17

• GRP (Glass Reinforced Plastic)
• Carbon Fibre
• Kevlar

Question 18

What are the common uses of GRP?

Answer 18

vehicle bodies like boat hulls or canoes.

Question 19

What are the common uses of Carbon fibre?

Answer 19

Sports equipment and bike frames

Question 20

What are the common uses of Kevlar?

Answer 20

Body Armour

Question 21

What is reinforced concrete?

Answer 21

reinforced concrete is concrete which has been modified to withstand more tension, by adding a metal reinforcing rod in the middle of the concrete.

Question 22

What are the general characteristics of Particle-based composite materials?

Answer 22

• High strength in compression
• Good stability
• Uniform structure ensuring constant strength
• Generally free from surface defects

Question 23

What is concrete made out of?

Answer 23

Concrete is made up of aggregates, sand and cement

Question 24

What are some advantages of Concrete?

Answer 24

• Can be molded into complex shapes
• Similar properties to stone
• Can be cast in site
• Good in compression

Question 25

What is a disadvantage of concrete?

Answer 25

Poor in tension

Question 26

What is a cermet?

Answer 26

A mixture of metal and ceramic particles

Question 27

Give an example of an cermet

Answer 27

Tungsten carbine

Question 28

What are some advantages of using cermets?

Answer 28

- Resistant to high temperatures | - Tough and Shock resistant