1.5 Modern Composite & Emerging Technologies Flashcards
What are thermochromic materials?
Material which will change colours as a reaction to a change in heat.
What is used to get thermochromic effects?
Liquid crystals
Organic dyes, aka leucodyes
What are the uses of liquid crystals?
They give an accurate measurement of temperature
Used in calculator LCD screens
Thermometer strips
Battery power strips
Explain leucodyes (organic thermochromic)
A dye that starts at a base colour and changes once heat is applied.
A white receipt turns black when heated.
What is photochromic material?
Material that changes colour depending due ot exposure from different lighting conditions(mainly the UV rays from sunlight).
What is photochromic materials used in?
Nail varnish, camera filters, photochromic materials
What is phosphorescent materials and what are they used in?
Zinc sullied crystals mixed with copper that absorb light and slowly emit them overtime.
Glow in the dark objects.
What are holograms and what are they used in?
There are many types for different uses but they all mainly do the same things, take a portion of the light going through them and reflecting them back.
Used in windows to improve shatter resistance & privacy. Protect objects from UV Rays that degrade colours over time.
What are basic holograms.
2D layered image that under the right light conditions appears to be 3D.
What are the 3 types of holograms and their uses?
Reflection - Holograms which are illuminated with a white light at the back of it. X-Ray images.
Transmission - Illuminated from the back using a laser, provide very clear and sharp images. Star Wars holograms.
Embossed - hologram is on an aluminium foil which reflects light back through the hologram making it appear. Credit cards ro Driver Licenses.
What are Liquid Crystal Displays(LCDs) and what are there benefits compared to LEDs?
Liquid crystals placed between 2 sheets of glass. They use less energy and produce less heat than LEDs.
What is Polyether Ether Ketone(PEEK) and what is its uses?
Semi crystal thermoplastic, that can resist high temperatures(max. 280), tough, strong and rigid. Great heat conductivity.
Used in marine, automotive, medical and aerospace.
What is polyphenylsulfone(PPSU) and what is it used for?
It’s a very mouldable plastic that is used for rapid prototyping and rapid manufacturing.
What’s is graphene and what are its uses?
1 atom thick layer of pure carbon bonded together in hexagonal shapes. The strongest and most lightweight material there is. Incredible electrical and heat conductivity. It is hard to produce and obtain without harmful chemicals or damaging it tho.
Used in tyres. Potentially replace lithium ion and kevlar.
