1.11 Smart Materials Flashcards
Describe smart materials
Materials whose physical properties change in response to an input or change in the environment, such as electricity, pressure, temperature or light.
How does SMAs work?
Changes shape in a response to a change in temperature or electrical input
State two uses of SMAs
- Dental braces
- Self-closing windows
- Aeroplane wing flaps
- Bioengineering, such as stents, bone plates, screws
How does thermochromic pigment work?
Changes colour in response to temperature
State three uses of thermochromic pigment
- Room thermometers
- Medical thermometers, for children
- Bath water thermometers
- Colour change mugs and kettles
- Food packaging
- Baby feeding spoons
- Battery charge indicator strips
How does phosphorescent pigment work?
Absorb light energy during the day and ‘re-emits’ the light energy when it is dark
State two uses of phosphorescent pigment
- Fire exits signs
- ‘Glow in the dark’ products, such as adhesive stars, masks, night lights, and watch bands
How does photochromic pigment work?
Changes colour with light intensity
State two uses of photochromic pigment
- Welding goggles
- Reactive spectacle lenses
- Security marker that shows up under UV light
How does electroluminescent wire work?
Thin copper wire coated in a phosphorescent material that glows in response to an alternating current
State two uses electroluminescent wire
- Glow bracelets
- Interweaving for clothing
- Home decoration
- Outdoor decoration lighting
How does piezoelectric material work?
Gives off a small electrical charge when deformed
Increase in size (up to 4%) when an electrical current passed through it
State two uses piezoelectric material
- Airbag sensors in cars
- Vibration damping in tennis racquets
- Lighters for barbecues
- Musical greeting cards
- Pressure sensors
