Smart and Modern Materials Flashcards
What are smart materials and what are examples?
Smart materials are materials that change their properties in response to a stimulus or input such as light, heat, pressure, or electricity.
Examples
* Thermochromic pigments - Change colour due to a heat input.
-Baby feeding products – more accurate & hygienic.
-Flexible thermometer.
* Photochromic pigments - Change colour due to a light input.
-Reading/sunglasses - only need one pair
* Shape Memory Alloys Nitinol, Memoflex - Metals that revert back to their original shape at certain temperatures.
-Heat treated to give the metal a memory. Bio-engineering applications - Stent tube, chilled, inserted into artery. Plates for broken bones, dental braces.
-Memoflex glasses- superelastic alloys, squashed and return to original shape.
* Piezoelectric - Transform mechanical to electrical energy and vice versa
-Used for sensors- burglar alarm pressure mats
-Used as actuators – fast acting valves and nozzles
-Decorative – kids shoes with flashing lights
* Quantum tunnelling composites QTC - Change from an insulator to a conductor when pressure is applied
-Touch sensitive fabrics used as pressure sensors or switches.
-The user can operate electronic devices without actually touching them.
What are modern materials and what are examples?
Modern Materials are materials that have recently been developed for specific applications. They are discovered through extensive research and then a use found for them. Not smart materials. Can be used to replace traditional materials.
Examples:
* PMC –precious metal clay - Microscopic particles of gold/silver in a clay. Shaped then heated to remove binder
-PMC – used for jewellery – quicker, less expensive equipment
* Polymorph Polycaprolactone(PCL) - biodegradable , low melting point, remodelled using hot water
-Polymorph-used for modelling - Can create complex 3D shapes eg hand grips.
* Starch based polymers PLA, PHB, Polymorph - Biodegradeable
-Packaging- short life span, protects the environment if product goes to landfill.
-Modelling material
* Carbon fibre Kevlar - Yarn woven into a fabric, Combined with polymer resin – very strong but light.
-Bike frame, racing cars, tennis racket
-Bike tyres, bike helmet, stab/bullet proof vests
* Fibre optics - Thin strands of glass/plastic fibres, transmits light
-Data transmitted more efficiently than traditional copper cables.
-Lighting
* Breathable fabrics Goretex Sympatex - Porous membrane laminated to high performance textiles
-Walking and cycling clothes
* Maplex- Manufactured wood like MDF but 100% wood no resin, biodegradable.
-Furniture
-Used instead of MDF
