Materials and Components

Shape Memory Alloys (SMA)

• Change shape in reaction to a stimulus e.g. light, heat, pressure
• For example a wire which goes straight when a certain voltage is put through it
• Very expensive to make and not as strong as normal materials

Reactive Glass

• When there is a light source or heat source the glass goes dark
• Welding mask is clear until the sparks from the welding start and then the glass goes dark
• This is operated by electronics
• Can replace blinds in windows

Photochromic Paint

• Contains pigments that change colour according to light conditions
•  For example clear in the dark and pink under UV light
• A reversable reaction
• Security markers

Quantum Tunneling Composites

• In its relaxed state it is an electrical insulator
• When it is stretched, compressed or twisted it becomes an electrical conductor
• The greater the stress the more it conducts
• Can be used in pressure sensors and speed controllers