Week 4
Topic: Uses of Materials – Ceramics, Plastics and Rubber
Ceramics
Ceramics offer many advantages compared to other materials. They are harder and stiffer than steel; more heat and corrosion resistant than metals or polymers; less dense than most metals and their alloys; and their raw materials are both plentiful and inexpensive. Ceramic materials display a wide range of properties which facilitate their use in many different product areas.
- Aerospace: space shuttle tiles, thermal barriers, high temperature glass windows, fuel cells
- Consumer Uses: glassware, windows, pottery, Corning ware, magnets, dinnerware, ceramic tiles, lenses, home electronics, microwave transducers
- Automotive: catalytic converters, ceramic filters, airbag sensors, ceramic rotors, valves, spark plugs, pressure sensors, thermostats, vibration sensors, oxygen sensors, safety glass windshields, piston rings
- Medical (Bioceramics): orthopedic joint replacement, prosthesis, dental restoration, bone implants
- Military: structural components for ground, air and naval vehicles, missiles, sensors
- Computers: insulators, resistors, superconductors, capacitors, ferro-electric components, microelectronic packaging
- Other Industries: bricks, cement, membranes and filters, lab equipment
- Communications: fiber optic/laser communications, TV and radio components, microphones
Plastics
The relatively low density of most plastic materials means the end products are lightweight. They also have excellent thermal and electrical insulation properties. However, some can even be made as conductors of electricity when required. They are corrosion resistant to many substances which attack other materials, and some are transparent, making optical devices possible. They are also easy to mould into complex shapes and forms, allowing integration of different materials and functions. And in the event that the physical properties of a given plastic do not quite meet the specified requirements, the property balance can be modified with the addition of reinforcing fillers, colours, foaming agents, flame retardants, plasticisers etc., to meet the demands of the specific application.
For these reasons and more, plastics are increasingly used in:
Rubber
Most rubber is used for tyres for cars, large vehicles and planes. Rubber is also used to make many mechanical parts such as gaskets, belts and seals.
Rubber products include waterproof clothing, gloves, hats, shoes and household products. Medical equipment made of rubber includes hot water bottles, gloves, syringes, tapes, oxygen tents, hearing aids and many more. Swimmers wear goggles,caps and flippers made of rubber. Many sports have rubber equipment, such as golf balls and other rubber balls. Rubber products seal jars, are used in toys and paints and for recreation. Sponge and foam rubbers are used to make bedding and other furniture, cushions and pillows, and as insulation.