materials

• smart material = a material that can change its properties depending on the environment it is in

  • smart materials are modern materials, modern materials are not necessarily smart.
• modern material = a material that has been engineered to have improved properties close properties. The mechanical, physical or optical properties of materials that define how they behave in use.
• modern material e.g :

  Graphene

  • is a single carbon layer material, which is hypothetically 100 times stronger than steel

  structure of graphene is :

  
• modern material e.g :

  titanium

  • used in sporting and medical applications, such as replacement hip joints and high-performance bicycles.
  • it has a high strength-to-weight ratio and is resistant to corrosion.

  titanium hip placement :

  
• modern material e.g :

  metal foam

  • produced by injecting a gas or foaming agent (material that facilitates the formation of foam) into molten metal
  • used in vehicles such as planes and cars as they absorb shock effectively if the vehicle crashes.
• modern material e.g :

  nano materials

  • used in thin films or coatings such as the oleophobic coatings on smartphone screens that repel greasy fingerprints, or hydrophobicmaterials that repel water

  hydrophobic material

  
• smart materials e.g :

  shape memory alloy

  • it will remember its form when it is heated
  • braces for straightening teeth are made from Nickel titanium (nitinol), they heat up in the mouth and ‘pull’ on the teeth, so they move with the nitinol.
• smart material e.g :

  photochromic pigments

  • pigments change their properties when exposed to ultraviolet (UV) light
  • example would be glasses where the lens will be normal, clear indoors but when you go out in the sun it will become more like sunglasses
• smart material e.g :

  Polymorph

  • polymer that becomes malleable when heated to about 62°C
  • it cools down it becomes hard enough to drill and cut. This makes it perfect for modelling as it can be reheated and formed again. It is also excellent for creating ergonomic handles
• composite material = combination of two materials with different physical and chemical properties.

  • 3 example - fibreglass, chipboard, reinforced concrete
• ferrous material = Ferrous metals are defined as those metals that contain iron. Non-ferrous metals do not. 

  e.g. steel, cast iron and wrought iron
• hardwood = its trees are deciduous trees that drop leaves in winter. Hardwoods mainly have large broad leaves, which usually produce a seed or fruit

  
• softwood = they come from coniferous trees. These often have pines or needles, and they stay evergreen all year round - they do not lose leaves in the autumn. They are faster growing than hardwoods which makes them cheaper to buy, and are considered a sustainable.
• manufactured board = Manufactured board is a natural timber that is combined with adhesive to make a composite material. Examples include MDF, chipboard and hardboard.

  
• polymers = large molecules made from many monomers joined together by covalent bonds

  • Most polymers are synthetic, meaning they are man-made and have been designed by chemical engineers. Different polymers are created all the time so that the demands of the consumer can be met
  • 2 categories of them are thermosetting and thermoforming
  • mostly made using crude oil