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| Welcome to TecCeram > Materials |
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| Alumina |
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Alumina in its various degrees of purity is a versatile material that offers a combination of good mechanical and electrical properties and probably the most important oxide ceramic for widely varying technical applications. Depending on the alumina purity, particular the purity ranging from 95% to >99.7%, these aluminum oxide ceramics have variety of properties:
* Good mechanical strength
* Good heat conductivity
* Good fire resistance
* Good corrosion and wear resistance
* Good sliding properties
* Very good electric insulation
It is suitable for a wide range of applications including seal rings, laser tubes, electrical insulators, threadguides, refractory devices, electronic substrates, thermocouple tubes, grinding media and wear components. It has a good strength and stiffness, very high hardness and resistance to wear. In addition it can be readily joined to metals or other ceramics using specially developed metallising and brazing techniques. |
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| Yttria stabilized tetragonal zirconia |
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Zirconia naturally occurs in the form of the mineral baddeleyite. For ceramics purposes, however, it is extracted from zirconium sand and other minerals containing zirconium in order to satisfy high standards of purity.
Zirconia offers chemical and corrosion resistance at high temperatures up to 2100°C – well above the melting point of Alumina. In its pure form, crystal structure changes limit use in mechanical/temperature applications, but stabilised Zirconias with Ytrium Oxide or Magnesium additives can produce materials with very high strength, hardness and in particular, toughness. |
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| Magnesia partially stabilized zirconia |
Zirconia naturally occurs in the form of the mineral baddeleyite. For ceramics purposes, however, it is extracted from zirconium sand and other minerals containing zirconium in order to satisfy high standards of purity.
Zirconia offers chemical and corrosion resistance at high temperatures up to 2100°C – well above the melting point of Alumina. In its pure form, crystal structure changes limit use in mechanical/temperature applications, but stabilised Zirconias with Ytrium Oxide or Magnesium additives can produce materials with very high strength, hardness and in particular, toughness. |
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| Zirconia toughness alumina |
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Zirconia toughened alumina (ZTA) ceramic is a composite fine ceramic material, in which a certain content zirconia material is added inside to improve alumina comprehensive mechanical properties. Such kind of composite ceramic not noly have very high tougness and strength propoteries like zirconia, but also have very high hardness like alumina. Because of this high comprehensive property, ZTA ceramic has outstanding wear resistance. Reasonable component control and homogeneous structure of ZTA have very good property and was widely used in different application. |
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| Aluminum titanate |
Aluminum titanate material is produced in a special sinter process from high grade raw materials. During this well defined reaction process, a microporous material is formed with a unique property profile:
* Low thermal expansion
* Low thermal conductivity
* Low modulus of elasticity
* Excellent thermal shock behavior
* Good corrosion resistance
* Outstanding temperature resistance
* No or littlewettability in non-ferrous molten metals
Due to its unique grain structure (see below), aluminum titanate has almost no thermal expansion even at high temperatures. Combined with the very low modulus of elasticity Aluminum titanate has an outstanding thermal-shock resistance and can cope with abrupt temperature changes of several hundred degrees. Aluminum titanate is characterised by low thermal conductivity / good heat insulation, high chemical and wear resistance. |
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| Silicon Nitride |
Silicon Nitride has very good synthetical properties, such as extremely high strength, outstanding crack resistance, excellent wear and chemical resistance, good heat conductivity, very low heat expansion, excellent thermal shock capability (ie; cycles from RT to 750°C in 7 seconds and repeated every 30 seconds), not wetted by many metal and alloys, and electrically insulating. Due to these properties and its low weight, silicon nitride is a material for the highest demands. Silicon Nitride is produced in three main types: Reaction Bonded Silicon Nitride (RBSN), Hot Pressed Silicon Nitride (HPSN) and Sintered Silicon Nitride (SSN). RBSN gives a relatively low-density product compared with hot pressed and sintered Silicon Nitride. HPSN and SSN materials offer better physical properties suitable for more demanding applications. Typical Applications include:
* Molten metal handling (including crucible / wear plates)
* Induction heating coil supports
* Welding nozzles, fixtures and weld location pins
* Dental heat treatment supports
* Thermocouple sheaths
* Bearings and rollers
* Glow plugs
* Cutting tools |
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