DEFINITION :

Glassy graphite is high temperature resistant in inert gas or vacuum up to 3000°C. Unlike all other ceramic and metallic high temperature materials, glassy graphite increase in strength with a rise in temperature up to 2400°C. Glassy graphite shows at 2400°C compared to room temperature the double strength. Compared to ceramic and metallic materials, glassy graphite shows even at high temperatures no embrittlement. In comparison to the most ceramic and metallic materials glassy graphite has an extremely high resistance to thermal shock. Therefore short heating and cooling times are possible without any problems. Further advantages are the low mass, low heat absorption and low thermal expansion.

GLASSY GRAPHITE CRUCIBLE MAIN CARATERISTICS :

Graphite crucibles obviate the disadvantages of ceramic crucibles such as low thermal conductivity, adhesion of noble metal melts and the need for melting salt.

With Graphite melting crucibles the heating and melting times are reduced. The electric heating coil of the melting unit can be operated at lower temperatures than those of traditional ceramic vessels. The time needed for each casting is thus reduced and the life of the crucibles extended. Graphite glassy carbon crucibles have a much longer life than graphite crucibles.

In addition, the absence of wetting eliminates the problems of material losses.

High purity, low specific surface and an isotropic structure cause a low and consistent oxidation generating a protective atmosphere over the metal melt. This low oxidation rate prevents the formation of an oxide layer on the molten metal.

The melting powder or pellets usually required with ceramic crucibles are not necessary as the melt runs out freely without wetting the crucibles wall.

The casting obtained has a uniform and neat appearance.

The metal-repellent properties of the crucible remain unchanged throughout the product life.

With their extremely good resistance to thermal shock, Graphite crucibles don't crack even if placed on cold surfaces when red-hot.
Graphite crucibles are also suitable for use in induction-heated casting centrifuges.

Since glassy carbon crucibles - unlike ceramic crucibles - couple in the inductive field and reach the operating temperature within a minimum of time, the metal will melt quickly and evenly.

Extensive tests have shown Graphite crucibles to be well suited to the task of melting high-palladium alloys. Graphite crucibles have also been employed for melting palladium-containing fused ceramic alloys with reduced noble metal content at temperatures around 1400°C.

Graphite crucibles are suitable for all noble metal and titanium alloys

The finished castings neither have cavities nor do they fade or flake after ceramic veneering.

Graphite crucibles should not be used for melting chromium-cobalt-molybdenum alloys (steel alloys).

ONLINE AVAILABLE PRODUCTS :

Cylindrical crucible
Evaporating dish
Conical crucible
Lid
Crystal growth crucible
Crucible with dispensing spout
Boat, incinerating dish