Classification of Materials

• ferrous metals


  a metal containing mostly iron and carbon.

  ferrous metals are magnetic and will rust.
• examples of ferrous metals

  low carbon steel, medium carbon steel, cast iron
• non-ferrous metals


  a metal that does not contain iron.

  Non-ferrous metals are not magnetic and do not rust
• examples of non-ferrous metals

  aluminium, copper, zinc, silver, gold, titanium, tin
• alloy


  a metal made up of two or more metals, or combining two or more elements, one of which must be a metal.

  these can be classified into ferrous alloys and non-ferrous alloys
• examples of alloys


  ferrous

  stainless steel, die steel

  
  

  non-ferrous

  bronze, brass, duralumin, pewter
• hardwood


  a wood from broad-leafed (deciduous) trees

  generally slow growing, lose leaves in autumn
• softwood


  a wood from a coniferous (cone bearing) tree

  generally fast growing and tend to be evergreens
• manufactured boards


  a man made wood based composite material

  available in much larger sizes than solid wood, not limited to the size of a tree trunk
• examples of hardwoods

  oak, ash, mahogany, teak, birch, beech
• examples of softwoods

  pine, spruce, douglas fir, redwood cedar, larch
• examples of manufactured boards

  plywood, marine plywood, aeroply, flexible plywood, chipboard, MDF
• thermoplastics polymers

  a material which can repeatedly be reheated and reshaped, allowing it to be recycles after initial use.

  they have long linear chain molecules held by van der walls forces
• Thermosetting polymers

  a material which when heated undergoes are chemical change whereby the molecules form rigid cross links.

  thermosetting polymers cannot be reheated or reshaped, even at very high temperatures
• elastomer


  a material which at room temperature can be deformed under pressure and then upon release of the pressure, will return to its original shape.

  elastomers have weak bonds which allow them to stretch easily. they can be stretched repeatedly and upon immediate release of the stretch will return to original shape
• examples of thermoplastics

  low density polyethylene (LDPE)

  high density polyethylene (HDPE)

  polypropylene (PP)

  high impact polystyrene (HIPS)

  acrylontrile butadiene styrene (ABS)

  polymethyl methacrylate (PMMA)

  polyethylene terephthalate (PET)

  nylon

  rigid and flexible chloride (PVC)
• examples of thermosetting plastics

  urea formaldehyde (UF)

  melamine formaldehyde (MF)

  polyester resin

  epoxy resin
• examples of elastomers

  natural rubber

  polybutadiene

  neoprene

  silicone
• paper and boards


  described as compliant materials, meaning they can be scored, folded and cut with basic tooling to form items such as nets for packaging
• examples of papers and boards

  layout paper, treated paper, cartridge paper, tracing paper, bleed proof paper, watercolour paper

  
  

  corrugated card, bleached card, mount board, duplex card, foil backed and laminated card, metal effect card

  
  

  moulded paper pulp
• composites


  a material comprised of two or more different materials, resulting in a material with enhanced properties
• examples of composites

  fibre based

  caborn fibre reinforced plastic (CFRP)

  glass fibre reinforced plastic (GRP)

  fibre concrete

  
  

  particle based - tungsten carbide, concrete

  
  

  sheet based - aluminium composite board, engineered wood (e.g., glulam)
• smart materials


  a material whose physical properties change in response to an input or change in the environment, such as electricity, pressure, temperature or light
• examples of smart materials

  shape memory alloy (SMA)

  thermochromatic pigment

  thermochromatic film

  phosphorent pigment

  photochromic pigment.

  electroluminescent wire

  piezoelectric material
• modern materials


  a material developed through the invention of new or improved processes

  e.g., as a result of man-made materials or human inventions

  
  

  *they are not smart because they do not react to external change
• examples of modern materials

  kevlar

  precious metal clay (PMC)

  high density modelling foam

  polymorph
• material disposal


  - material disposal at end of life is a huge consideration

  - influences manufacturers material choice and consumer choice

  - influence choice of environmentally aware consumers