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Design & Technology

Materials

Smart materials

Smart materials are reactive materials. Their properties can be changed by exposure to stimuli, such as electric and magnetic fields, stress, moisture and temperature.

Smart colours

Smart colours are pigments which can be incorporated into paints, dyes, inks and plastics.

  • thermochromic pigments react to changes in temperature
  • photochromic pigments react to changes in light levels

Photochromatic materials are used in the manufacture of sunglasses. Exposure to sunlight causes the lens of the glasses to darken to protect the eye.

Polymorph

Polymorph is available in small pellets which fuse together when heated to 62˚C. It can be moulded into shape resulting in a very tough polymer. Unused pellets can be re-heated and re-used.

Polymorph is used for:

  • manufacturing awkward shapes such as ergonomic [ergonomics: The science of designing the product to fit the user, or the job to fit the worker. ] handles
  • joining components together
  • making moulds for vacuum forming

Smart grease

Smart grease is used to control movement, producing a dampened, slowed down feeling. For example, smart grease is used on volume control knobs and microscope slides.

Conductive polymers

Most plastics are natural insulatorsinsulator: Material that is a poor conductor of electricity or heat.. The advantages of making plastics which are conductorsconductor: An electrical conductor is a material which allows an electrical current to pass through it easily. It has a low resistance. A thermal conductor allows thermal energy to be transferred through it easily. are:

  • they are easier to manufacture
  • they are lighter and cheaper than metals
  • they prevent the build-up of static electricity which can damage microcircuits

Some conductive polymers are also biocompatible [biocompatible: Can be safely used in the body. ], making them suitable for use in medical devices.

Nanomaterials

Nanoparticles improve the mechanical properties of a material, such as stiffness or elasticity [elasticity: The ability of a fibre, yarn or fabric to stretch and return to its original shape. ]. When incorporated into polymers, they can be used as lightweight replacements for metals.

Nanomaterials are used in car manufacturing to create cars that are faster, safer and more fuel efficient. They can also be used to produce more efficient insulation and lighting systems.

Back to Resistant materials index

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