Ceramic Alloy Materials

Ceramic materials are inorganic, non-metallic solids. They may be crystalline or amorphous in nature, and are prepared by giving appropriate heating and cooling treatment to these materials. Technically, these can be defined as inorganic oxides, non-oxides or particulate materials that are generally crystalline in nature. The most commonly seen ceramic materials are the pottery and bricks that are made from clay, although they have now found many new uses in engineering, semiconductor industry, tooling, ballistic, gas turbine engines, watches, dental implants, synthetic bones and space equipments.

Ceramic Alloy Materials

Ceramics can broadly be classified into oxides, non-oxides and composites.

Oxide Ceramics

Oxide ceramics – such as alumina or zirconia – are resistant to oxidation, do not react chemically, are good electrical and thermal insulators. These are required to be extremely pure and the manufacturing process is therefore elaborate and complex enough to ensure that no impurities that can significantly alter the properties of these ceramics are left behind. Further, heat treatments for these ceramic materials are attuned to give them a specific crystal structure.

Non-oxide Ceramics

Non-oxide ceramics – like carbides, borides, nitrides or silicides – are typically more prone to oxidation, very hard but chemically un-reactive, and also have good thermal and electrical conductivity properties. Manufacturing non-oxide ceramic materials is generally a three step process, where the required non-oxides are firstly prepared, then mixed into a desired powder and finally heat treated in a controlled oxygen-free environment.

Composites

Composites are a combination of oxides and non-oxides, which have been reinforced together using some particulate matter. They are generally tough and are costly to manufacture, while their conductivity and oxidation resistance will vary on the exact composition. It is possible to prepare a wide variety of such composite ceramics (based on what is the combination of oxides, non-oxides, polymers that are reinforced together), with the objective to tune the toughness, hardness or conductivity that is appropriate for a required condition or application.

Some Examples of Ceramic Materials

Ferrite Magnets, classified as ceramics, are inexpensive permanent magnets. They are however very brittle and should therefore not be used in structural applications. They also have a relatively low thermal tolerance and begin to break down around 300C. These are prepared using iron oxide and strontium or barium oxide, compressed together along with some ceramic binder.

BAM is a ceramic material that contains boron, aluminum, magnesium and titanium boride. It is one of the hardest and smoothest known materials, and finds application in all places that require hard materials that are wear resistant and need frictionless environments (such as coatings on moving parts of equipments and machines). It is licensed an Iowa based company, Des Moines.



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