Smart Materials Flashcards
Smart materials
Materials whose physical properties change in response to a stimulus or change in the environment. When the stimulus is removed the physical properties return to what they were originally
Shape memory alloys (SMA)
Alloys that change shape in response to electrical input or temperature change
E.g. Nitinol wire in dental braces changes length in response to temperature - tightens when in the patients mouth
SMA uses
Dental braces
Self - closing windows
Aeroplane wing flaps
Bioengineering - stents, bone plates and screws
Thermochromic pigment
A pigment that changes colour in response to a change in temperature
Uses of thermochromic pigments
Room thermometers
Medical thermometers
Bath water thermometers
Baby feeding spoons
Battery charge indicator strips
Phosphorescent pigment
Absorbs light energy during the day and re-emits the light energy when it’s dark
Uses of phosphorescent pigment
Fire exit signs
Glow in the dark products - watch hands, glow sticks, night lights
Photochromic pigment
A pigment which changes colour in response to changes in light intensity
Uses of photochromic pigment
Welding goggles
Reactive spectacle lenses
Security markers - only show in UV light
Electroluminescent wire
Thin copper wire coated in phosphorescent material that glows in response to an alternating current
Uses of electroluminescent wire
Glow bracelets
Outdoor decorative lighting
Home decorations
Piezoelectric material
A material which gives off a small current when deformed
Increases in size (up to 4%) when a current is passed through it
Uses of piezoelectric material
Airbag sensors in cars
Lighters
Pressure sensors
Examples of smart materials
SMAs
Thermochromic pigment
Phosphorescent pigment
Photochromic pigment
Electroluminescent wire
Piezoelectric material
