Many customers have inquired about sealing gaskets that require a temperature of 1000 ℃. To be honest, there are too few materials that can be used in such ultra-high temperature environments In the extremely high temperature environment of 1000 degrees, many sealing materials we know have already melted

Metal materials can reach this temperature, but using metal as a gasket is not suitable At present, there are two materials that can be used in ultra-high temperature environments above 1000 degrees: pure graphite and ceramic fiber Let's analyze these two materials in detail below

1. Pure graphite soft, black gray; Greasy and can contaminate paper. The hardness is 1-2, and it can increase to 3-5 along the vertical direction with the increase of impurities. The specific gravity is between 1.9 and 2.3. The specific surface area ranges from 1-20m2/g, and under oxygen isolation conditions, its melting point is above 3000 ℃, making it one of the most temperature resistant minerals. It can conduct electricity and heat.

Due to its unique structure, graphite has the following special properties:

1) High temperature resistance: The melting point of graphite is 3850 ± 50 ℃, and the boiling point is 4250 ℃. Even after being burned by ultra-high temperature arc, the weight loss is very small, and the coefficient of thermal expansion is also very small. The strength of graphite increases with temperature, and at 2000 ℃, the strength of graphite doubles.

2) Conductivity and thermal conductivity: The conductivity of graphite is one hundred times higher than that of typical non-metallic minerals. Thermal conductivity exceeds that of metal materials such as steel, iron, and lead. The thermal conductivity decreases with increasing temperature, and even at extremely high temperatures, graphite becomes an insulator.

3) Lubrication: The lubrication performance of graphite depends on the size of graphite flakes. The larger the flakes, the lower the friction coefficient, and the better the lubrication performance.

4) Chemical stability: Graphite has good chemical stability at room temperature, and can resist acid, alkali, and organic solvent corrosion.

5) Plasticity: Graphite has good toughness and can be rolled into very thin sheets.

6) Thermal shock resistance: Graphite can withstand drastic temperature changes without damage when used at room temperature. When the temperature suddenly changes, the volume of graphite does not change significantly and will not crack.

In practical applications, pure graphite gaskets are used at temperatures ranging from -200 to 650 degrees Celsius (with a maximum usage temperature of 450 degrees Celsius in oxidizing environments) So flexible graphite sealing gaskets cannot be used in environments with temperatures exceeding 1000 degrees Celsius

2. Ceramic fiber gasket is a non brittle material with high strength, accurate size, and can be made in various forms according to customer needs. It has good fire resistance and insulation effect and can be directly ignited. The classification temperature is 1050-1600 ℃.