Ceramic temperature resistance

Naturally, fibers and whiskers are of little use unless they are bonded together to take the form of a structural element that can carry loads. The binder material is usually called a matrix (not to be confused with the mathematical concept of a matrix). The purpose of the matrix is manifold support of the fibers or whiskers, protection of the fibers or whiskers, stress transfer between broken fibers or whiskers, etc. Typically, the matrix is of considerably lower density, stiffness, and strength than the fibers or whiskers. However, the combination of fibers or whiskers and a matrix can have very high strength and stiffness, yet still have low density. Matrix materials can be polymers, metals, ceramics, or carbon. The cost of each matrix escalates in that order as does the temperature resistance. 

Glass Ceramic fibers and particles Mechanical strength Temperature resistance Chemical resistance Thermal stability... 

Fiber reinforced ceramics such as C/SiC, SiC/SiC can be manufactured by the polymer infiltration and pyrolysis technique at reasonable cost. The developed production technique allows the manufacturing of large and complex structures comparable to fiber-reinforced plastics. The material has excellent high temperature resistance, low density, and good damage tolerance, and is therefore well... 

Refined niobium metal is most useful as an alloy with other metals. It is used to produce special stainless steel alloys, to make high-temperature magnets, as special metals for rockets and missiles, and for high- and low-temperature-resistant ceramics. Stainless steel that has been combined with niobium is less hkely to break down under very high temperatures. This physical attribute is ideal for construction of both land- and sea-based nuclear reactors. 

Reinforcements in the form of continuous fibres, short fibres, whiskers or particles are available commercially. Continuous ceramic fibres are very attractive as reinforcements in high-temperature structural materials. They provide high strength and elastic modulus with high temperature-resistant capability and are free from environmental attack. Ceramic reinforcement materials are divided into oxide and non-oxide categories, listed in Table 3.1. The chemical compositions of some commercially available oxide and non-oxide reinforcements are given in Table 3.2 and Table 3.3. 

Materials such as engineering ceramics or hard metal mixtures are becoming increasingly popular because they are very hard, wear-, and temperature-resistant. Injection molding technology, which is widespread in the plastics processing industry, is becoming established... 

Most porous membranes used in CMRs are made from oxide materials, although carbon membranes have also been used [1, 14, 22], However, although they possess very good separative properties, they have received less attention in CMR applications, probably due to their limited resistance to oxidative atmospheres. Vycor glass membranes also have certain drawbacks (brittleness, lack of high-temperature resistance) [9] for use in CMRs. Porous membranes in CMRs are, most often, made from ceramic materials or, more recently, from zeolites. 

High purity binary oxides such as BeO, MgO, AI2O3, Ti02, And stabihzed zirconia are sintered under pressure to produce high density ceramic ware, particularly cracibles and other containers for use in nonferrous metallurgy and other specialized applications where temperature resistance and corrosion are a problem. Titania is also formed in honeycomb arrays for use as catalyst supports. 

Different applications generally require different filter properties (temperature resistance, pressure drop, filtration efficiency, etc.), and therefore a number of different types of filters, based on either ceramic (SiC, mullite, cordierite, etc.) or metallic (stainless steel, Hastelloy, Fecralloy, etc.) materials, are currently produced and commercialized. Table 1 summarizes such filter types, their producers, and their major application fields. 

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