Because rare-earth element has structure of 4fx5d16s2 electronic shell, electrovalency tall, radius force of big, polarization strong, chemistry is lively reach can the property such as hydrolysis, its use reason very extensive, have wide development perspective in special type pottery and porcelain and functional data side especially.

Si3N4 pottery and porcelain

Hardness of Si3N4 pottery and porcelain tall, intensity is big, hot coefficient of expansion is small, have the taller denaturation that fight squirm to be able to be reached fight oxidation, corrosion resistance can, it is material of a kind of first-rate high temperature construction. Regard Si3N4 as pottery and porcelain, as a result of Si - N key belongs to covalent bond, cause it is very difficult that in the photograph that do not have fluid existence issues agglomeration, must add additive. Relatively ideal additive is Y2O3 of rare earth oxide, CeO2, La2O3, can make Si3N4 pottery and porcelain produces fluid photograph when agglomeration not only, stimulative agglomeration, the high temperature that can raise Si3N4 pottery and porcelain greatly again at the same time is mechanical function. Consider to make clear, the nitrogen that adds La2O3 and Y2 O3 changes silicon pottery and porcelain, its bending strength keeps changeless below the high temperature of 1370 ℃ , amount to 1000MPa above. The Si3N4 pottery and porcelain that adds Al2O3 and La2O3 agglomeration auxiliary is formed have tall fireproof degree of Y with viscosity - Ls - Si - O - N glass crystal boundary, because this has higher high temperature,bending strength is mixed better fight oxidation function, the crystallization compound that and below high temperature condition Yi Xi gives taller frit nods, reduced material to be not the content of photograph of brilliant condition glass then, the high temperature that raised material ruptures tenacity.


Al2O3 pottery and porcelain

Al2O3 pottery and porcelain has taller hardness and mechanical strength, coefficient of expansion and metal are about the same, have good chemical stability at the same time. Will tell to Al2O3 pottery and porcelain, to increase thermal stability of its high temperature, can add rare-earth element. Consider to make clear: Can increase thermal stability of high temperature of Al2O3 pottery and porcelain, main reason was to form acerbity salt of rare earth aluminium, if add,La2O3 can form the LaAl11O18 that removes stabilization.
Be those who reduce Al2O3 pottery and porcelain is firing temperature, improve product performance, the rare earth additive of different amount is added in its, can fall greatly low fever becomes temperature.


SiC pottery and porcelain

SiC is the compound with covalent bond extremely strong sex, still can retain high bond strength below high temperature condition, and hot coefficient of expansion is small, corrosion resistance is admirable, have taller hot conductibility, reason is one of material with the most hopeful material of high temperature construction.
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