Composites+ modern materials

Composites+ modern materials

1. each year hundreds of new materials are developed

   • either due to new technology
   • or a push from a designer
     • e.g If existing materials do not have the desired properties for a prospective product

2. improve properties- by combining materials

   • composite
     • different to an alloy, as in a composite the materials are not chemically bonded together
       • if you cut through a composite, you can still see the different elements
     • have been used for over 6000 years
       • wattle and dawb
     • reinforced concrete
       • steel is used to improve tensile strength
         • used in buildings esp skyscrapers
     • glass- reinforced plastic
       • (GRP) fibreglass
         • glass fibres in a matrix of epoxy or polyester resin
           • light + stronger than plastic- canoes
     • carbon fibre reinforced plastic
       • CFRP
         • strength of carbon fibre + rigidity of polyester resin
           • racing bikes and helmets
     • these are made using strands of fibre in a matrix of liquid resin, which hardens to form the composites
     • difficult to separate elements in a composite
       • and not cost-effective to try
         • so they can't be recycled, have to be thrown away-landfill
           • thus, many people believe that composites are not environmentally friendly materials

3. nanotechnology

   • the science of the very small
     • particles made from it have dimensions less than 100 nanometres
   • nano-composites
     • can be combined with other materials to improve properties
       • e.g
         • glass can be coated with a layer of nanomaterials that repel water and dirt- windows that never need cleaning
         • carbon nanotubes can reduce the weight of CFRP, without reducing its strength
           • e.g reducing weight of tennis frames + high performance racing bikes
     • currently quite expensive to make
     • risk that if released into environment, could cause novel types of pollution
       • altho, ofc, some may be developed which help the environment
   • controlling matter on an atomic scale, to form it into new materials with diff properties