1.2-Smart materials

Question 1

What are smart materials

Answer 1

Materials whose physical properties change in response to an input or change in the environment, such as electricity, pressure, temperature or light

Question 2

SMAs e.g. ninitol - how does it work

Answer 2

• change in shape in response to a change in temperature or electrical input e.g. ninitol wire in response to a change in temperature
• if SMA is heated to a certain temperature it will return to its original shape

Question 3

SMAs e.g. ninitol - uses

Answer 3

-dental braces, self closing windows, aeroplane wing flaps

Question 4

Thermochromic pigment - how does it work

Answer 4

changes colour in response to a temperature change

Question 5

Thermochromic pigment - uses

Answer 5

-room thermometers, medical thermometers for children, colour change mugs, food packaging

Question 6

Phosphorescent pigment - how does it work

Answer 6

absorbs light energy during the day and ‘re emits’ the light energy when it is dark

Question 7

Phosphorescent pigment - uses

Answer 7

-fire exit signs, ‘glow in the dark’ products e.g. night lights

Question 8

Photochromic pigment - how does it work

Answer 8

changes colour with light intensity

Question 9

Photochromic pigment - uses

Answer 9

-welding goggles, reactive spectacle lenses

Question 10

Electroluminescent wire - how does it work

Answer 10

Thin copper wire coated in a phosphorescent material that glows in response to an alernating current

Question 11

Electroluminescent wire - uses

Answer 11

-glow bracelet, interweaving for clothing, outdoor decorative lighting

Question 12

Piezoelectric material - how does it work

Answer 12

• gives off a small electrical change when deformed

- increases in size (up to 4%) when an electrical current is passed through it

Question 13

Piezoelectric material - uses

Answer 13

-airbag sensorts in cars, lighters for barbecues, pressure sensors