Smart materials Flashcards
Smart materials def
Smart materials are materials whose physical properties change in response to an input or change in the environment, such as electricity, pressure, temperature or light. Many products utilise smart materials, often bringing benefits such as increased safety and/or ease of use.
What are all the smart materials?
Shape memory alloy, Thermochromic pigment, Phosphorescent pigment, Photochromic pigment, Electroluminescent wire, Piezoelectric material
How does a Shape Memory Alloy work?
Changes shape in response to a change in temperature or electrical input.
For example, nitinol wire in dental braces changes length in response to a change in temperature.
How does a thermochromic pigment work?
Changes colour in response to temperature change.
How does a phosphorescent pigment work?
Absorbs light energy during the day and ‘re-emits’ the light energy when it is dark.
How does a photochromic pigment work?
Changes colour with light intensity.
How does a electroluminescent wire work?
Thin copper wire coated in a phosphorescent material which glows in response to an alternating current.
How does a Piezoelectric material work?
Gives off a small electrical charge when deformed.
Increases in size (up to 4 per cent) when an electrical current is passed through it.
Uses of Shape Memory alloys
Dental braces, self-closing windows, aeroplane wing flaps, bioengineering such as stents, bone plates and screws
Uses of thermochromic pigments
Room thermometers, medical thermometers for children, bath water thermometers, colour change mugs and kettles, food packaging to indicate food is hot to eat or cool for drinks, baby feeding spoons, battery charge indicator strips
Uses of phosphorescent pigments
Fire exit signs, ‘glow in the dark’ products such as adhesive stars, masks, night lights, watch hands
Uses of photochromic pigments
Welding goggles, reactive spectacle lenses, security markers that show under UV light
Uses of electroluminescent wires
Glow bracelets, interweaving for clothing, home decoration, outdoor decorative lighting
Uses of piezoelectric material
