Composites And Smart Materials

Question 1

Benefits of LCDS

Answer 1

Require less power reducing need for replacing batteries (energy efficient)
No glare
Compact and so does not take up much room
High resolution

Question 2

What are shape memory alloys?

Answer 2

Change shape in response to a change in temperature or electrical input.

Question 3

Use of SMAs

Answer 3

Air conditioning
Fire alarm
Braces- nitinol changes length in response to change in temp. Be made to change at body temp so have constant tension in mouth

Question 4

What are thermo-ceramics?

Answer 4

Metal placed in a mould under high pressure forcing particles to bond. Hard surface finish and very high melting point. Also strong and lightweight.
Hard and stable at high temperatures

Question 5

Uses of thermonceramics

Answer 5

Turbine blades in jet engines
Brake discs
Tips on cutting tools

Question 6

What is reactive glass

Answer 6

React to a change in temperature by changing tint
As glass gets hot the glass darkens to block heat entering through

Question 7

Uses of reactive glass

Answer 7

Apartment windows
Glass roofing
Windows
Conservatories

Question 8

What is a photochromic material?

Answer 8

Material that changes colour depending on light intensity to protect user or help
They block UV light
Can reduce glare

Question 9

Uses of photochromic material

Answer 9

Welding goggles
Security markers that show under UV light
Lenses

Question 10

What is a thermo-chromic material?

Answer 10

A material that changes colour in response to heat

Question 11

Examples of thermo chromic materials?

Answer 11

Thermometers
Colour changing mugs and kettles
Baby spoons

Question 12

Describe the layup process

Answer 12

Manufacture the mould (1)
• Apply release agent / polish / wax to the mould (1)
• Gel coat mixed/ resin mixed (1)
• Gel / resin coat applied (1)
• Add / spray a layer of glass fibre (1)
• Add a layer of resin
Repeat for subsequent layers (1)
• Allow to set / cure (1)
• Remove and trim

Question 13

What does GTC stand for?

Answer 13

Quantum tunnelling composites

Question 14

What is a quantum tunnelling composite?

Answer 14

Insulating rubber containing tiny metal particles
Pressure or force sensing
When under pressure material changes from insulating to conducting

Question 15

Uses for QTCs

Answer 15

Touch screen technology
Speed controllers
Smart phone buttons

Question 16

Name some examples of composites

Answer 16

MDF
Plywood
Chipboard
Glass reinforced plastic
Carbon fibre reinforced plastic
Hardboard

Question 17

What are the properties of CFRP?

Answer 17

Lightweight
Corrosion resistant
Hard
Good compressive strength

Question 18

Uses of CFRP

Answer 18

Sports equipment
Prosthetics
Helmets
Fishing rods

Question 19

Glass reinforced plastic properties

Answer 19

Lightweight
Corrosion resistant
Tough
Hard
Low thermal expansion
Good compressive strength

Question 20

Uses of GRP

Answer 20

Boat hulls
Pond liner
Sports car bodies

Question 21

What is CFRP and GRP made up of?

Answer 21

Carbon fibres and polyester resin
Glass fibres and polyester resin

Question 22

What is MDF used for?

Answer 22

Model or mould making
Furniture items like bookcases
‘Flatpack’ furniture

Question 23

Properties of MDF

Answer 23

Easy to cut and shape
Good strength in all directions
Two smooth faces
Standard grade or veneered

Question 24

Uses of hardboard

Answer 24

Wardrobe backings
Peg boards
Clipboards

Question 25

Properties of hardboard

Answer 25

One shiny side
Does not split easily
Tough

Question 26

Properties of chipboard

Answer 26

Composite of wood chips and urea formaldehyde
Strength in all directions
Easy to cut
Not attractive in base form

Question 27

Plywood properties

Answer 27

Thin layers of wood placed at 90 degrees to each other and compressed
Strength in all directions
No grain weakness
Odd number of layers

Question 28

Uses of chipboard

Answer 28

Kitchen worktops and units
Shelving
Flatpack furniture

Question 29

Plywood uses

Answer 29

Stirctural work
Floorboards
Indoor furniture

Question 30

What can composites like GRP and CFRP do that standard materials like wood and metals can’t?

Answer 30

Easily moulded into complex shapes using lay-up method
These shapes are lightweight with good strengthens and toughness throughout

Question 31

What is nitinol an example of? What does it do?

Answer 31

A shape memory alloy
When heated to a certain temperature it will return to its original shape
Heat required around 70 degrees so done simply in hot water
Transition temp can be changed by supplying a current making it suitable braces in mouth without losing tension

Question 32

Disadvantages of LCDs

Answer 32

Limited viewing angle and brightness
Requires external light source in order to see it

Question 33

What does composite mean?

Answer 33

Material composed of different materials to maximise physical and mechanical properties

Question 34

Benefits of thermochromic materials

Answer 34

Detect if bath too hot for kids
Detect of drink too hot
Ability to see if food is hot

Question 35

Benefits of reactive glass

Answer 35

Retains heat, reducing heating costs
Keeps rooms cool too

Question 36

Benefits of QTM technology

Answer 36

Maximise screen space
Remove need for buttons
Touch screen ideology
More interactive
Increased versatility
Innovative design, increases understanding of technology

Question 37

Benefits of thermo-ceramics

Answer 37

High heat resistance (will not deform or expand)
Hard
Does not wear
Lightweight