BTEC First Engineering Learning aim B Know about developments in engineering materials and technologies Learning aim B is concerned with modern materials and processes. 1

Modern and smart materials BTEC First Engineering Modern and smart materials Usually a combination of two or more separate materials, which are bonded together Composite materials Materials that react to changes in the environment. They often have a ‘memory’. Smart materials Teacher notes (PS 6): Composites – materials such as carbon fibre, plywood, glass reinforced plastic (GRP) etc., where two different types of material are bonded together – e.g. GRP often consists of strands of glass and polyester resin. Smart materials – materials such as shape memory alloys that can return to their original shape after they have been heated. High performance materials – materials developed for specific tasks, such as having excellent strength at high temperatures for aircraft turbine blades. Materials with special properties that make them especially useful. They could be very light, but also very strong. High performance materials © Pearson Education Ltd 2012. Copying permitted for purchasing institution only. 2

Modern materials and processes BTEC First Engineering Modern materials and processes Metal foams Powder metallurgy Metal foams are cellular structures made with metal rather than polymers. They are often used as soundproofing in vehicles, or as crash protection. In electronics they can be used as heat sinks. A fine metal powder is compacted into the shape required, then heated in a controlled way to bond the particles together. Powder metallurgy is used to make complex designs. Teacher notes (PS 7): Metal foams – most are made from aluminium, although steel can also be used. There are many benefits of metal foams, including a very good strength-to-weight ratio. Powder metallurgy – although complex shapes can be produced, there is often a need to perform secondary machining processes to provide true surfaces, or if a thread is needed in a component part. © Pearson Education Ltd 2012. Copying permitted for purchasing institution only. 3

Often used in the communications sector, have replaced copper wires. BTEC First Engineering New technologies Optical fibres Telematics Often used in the communications sector, have replaced copper wires. Combines ICT with communications technology to allow vehicles to be tracked. Hydrogen fuel cells Blended wing bodies Chemical energy in hydrogen is converted to electricity. Now an alternative to petrol engines. Advanced aircraft designs consisting of large aerofoil wings joined to an aircraft body. Surface nanotechnology Teacher notes (PS 8): Optical fibres – replaced copper wire. Much faster speeds, with greater bandwidth. Much more information can be transmitted along the same size of cable. Hydrogen fuel cells – the energy produced is clean, with only heat and water as waste products. Engines that use hydrogen fuel cells are quieter and more simple than petrol or diesel engines. Surface nanotechnology – different chemicals can be used on materials to give them differing surface properties. One good example is self-cleaning windows. Telematics – similar to satellite navigation systems, a telematics system can be used to track locations of vehicles by using GPS references and ICT systems combined. Blended wing bodies – different from ‘flying wing’ designs. These aircraft have a distinct wing and body, although much more aerodynamic than existing designs. Bionics – small electronic devices can be used for medical purposes to improve the medical condition of individuals. A pacemaker fitted to regulate a person’s heartbeat is a good example. Bionics Chemical coatings are applied to the surface of materials to improve their properties. Medical problem solutions using small devices that combine electronics and mechanisms. © Pearson Education Ltd 2012. Copying permitted for purchasing institution only. 4