| Category | Type | ||
| Ceramics | Alumina Ceramics Carbide Ceramics Nitride Ceramics Oxide Ceramics Refractory Ceramics Silicon Carbide Ceramics Silicon Nitride Ceramics Traditional Ceramics Zirconia Ceramics |
Ceramics are inorganic non-metallic materials. Metal oxides (Al2O3, FeO, etc.) are common examples of ceramics, but other compounds such as carbides and nitrides are also included. Porcelain, glass, bricks and refractory materials are some examples of traditional ceramics. In the last 30 years, advances in material science have transformed formerly brittle ceramics into materials tough enough to withstand engine environments. Ceramics are used in a variety of applications including window glass, implantable components, cutting tools, valves, bearings, brake disks and chemical-processing equipment.
The properties for which ceramics are most often selected include:
High temperature resistance (High melting temperatures)
High electrical resistivity (Although some ceramics are superconductors)
Broad range of thermal conductivity (Some ceramics are good insulators)
High hardness (Many ceramics are brittle)
Good chemical and corrosion resistance
Low cost of raw materials and fabrication for some ceramics
Good appearance control through surface treatments, colorization etc.
Ceramics are generally more brittle than metals and can have similar stiffness (modulus of elasticity) and similar strength, particularly in compression. But in a tensile test they are likely to fail at a much lower applied stress. This is because the surfaces of ceramics nearly always minute cracks (Griffith cracks), which magnify the applied stress. Since ceramics often have high wear-resistance and hardness, most ceramic parts are formed as near net shape as possible. Ceramics are most often produced by compacting powders into a body which is then sintered at high temperatures. During sintering the body shrinks, the grains bond together and a solid material is produced. Other ceramic forming processes include: Dry pressing, Isostatic Pressing, Roll Compaction, Continuous Tape Casting, Slip Casting, Extrusion, Injection Moulding, Pre-Sinter Machining, Hot-Pressing, Hot-Isostatic Pressing, Grinding, Lapping and Polishing. Ceramics are generally separated into the following categories: Metallic Oxides, Glass Ceramics, Nitrides and Carbides, Glass, Carbon and Graphite, Porcelain and Ceramic Fibres.
Ukrainian inventor Johan De Broyer has conceived the idea for a re-sealable aluminum soda can read more
Richard Vennix MSc
co-founder of Matbase and innovation consultant
08-12-2009 08:33
Last november was a memorable month for us at Matbase, we passed the milestone of 1000 visitors per day. So I guess we were not that far of when we thought it would be a good idea to make the material database we used as students during our stay at the Delft University of Technology accessable to other people. Apparently, people appreciate the easy way they can lookup the material properties and how we present the data.
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