High-temperature structural ceramics   

High-temperature structural ceramics are high-temperature structural materials used in some devices, or equipment, or structures that can withstand static or dynamic mechanical loads under high temperature conditions.

Metals have been widely used as structural materials. However, because metals are susceptible to corrosion and are not resistant to oxidation at high temperatures, they are not suitable for high temperatures working conditions.

The high-temperature structural ceramics makes up for the weaknesses of metal materials. They have the advantages of high temperature resistance, none oxidation, acid and alkali corrosion resistance, high hardness, wear resistance, and low density. Therefore, they have been increasingly developed and applied.

High-temperature structural ceramics include high-temperature oxides and high-temperature non-oxides (or refractory compounds):

High-temperature oxide structural ceramics refer to oxides with a melting point above 1728° C. (eg, silicon oxide crystals) or certain composite oxides (eg, alumina, zirconia, magnesia, calcia, yttria, etc.).

Their important feature is good chemical stability at high temperatures, especially good oxidation resistance. However, the weakness is that the brittleness is large and the mechanical impact resistance is poor.

In recent years, zirconia toughened alumina has improved fracture toughness parameters from 2.9 MPa/m2 to 15 MPa/m2 and flexural strength from 350 MPa to 1200 MPa.

With yttrium-stabilized zirconia, the fracture toughness parameters are as high as 9 to 16 MPa/m2.

Toughened oxide ceramics can be used to make hammers, fruit knives, scissors, shafts, and engine parts that can withstand certain shocks without breaking.

High-temperature oxide ceramics can be used as high-temperature furnace linings, crucibles for melting rare metals and pure metals, and high-temperature electrode materials and heat engine materials for magnetic fluid power generation devices.