11 - Smart materials - Classification

Question 1

Shape Memory Alloys

Answer 1

E.G Nitanol

Changes shape in response to a change in temp or electrical input

Used in dental braces, self closing windows, aeroplane wing flaps. Medical use in bone plates and screws

Question 2

Thermochromic pigment

Answer 2

Changes colour in resposnse to a temperature change

Thermometers, colour changing mugs, foot packaging to indicate food is too hot to eat, baby feeding spoons

Question 3

Phosphorescent pigment

Answer 3

Absorb light energy during the day and re-emits the light energy when it is dark

Fire exit signs and other glow in the dark products. E.G ceiling stars, watch hands

Question 4

Photochromic pigment

Answer 4

Changes colour with light intensity

Welding goggles, reactive glasses lenses, photochromic windows

Question 5

Electroluminescent wire

Answer 5

Copper wire coated in a phosphorescent material that glows in response to an electric current

Outdoor decorative lighting, decoration, woven in to clothing

Question 6

Piezoelectric material

Answer 6

Gives off a small electrical charge when deformed

Increases in size when an electrical current is passed through it

Airbag sensors in cars, shock absorbtion in tennis racquets Musical greetings cards.