Know about graphite crucibles

Update:11-05-2019
Summary:

Graphite crucible has good thermal conductivity and hig […]

Graphite crucible has good thermal conductivity and high temperature resistance. During high temperature use, the coefficient of thermal expansion is small, and it has certain strain resistance to rapid heat and rapid cooling.

The main use of graphite crucibles is to smelt copper, aluminum, gold, silver, lead, zinc and alloys and other non-ferrous metals and experiments. Because the melting point of the metal is high, other materials and ordinary ceramic crucibles will melt and do not meet the requirements, and the melting point of graphite is ideal at 3652 °C, and corrosion resistance and strength are good. Therefore, graphite crucible is the best vessel for melting non-ferrous metals, can withstand the melting temperature of most non-ferrous metals, does not occur at temperatures that cannot be reached, or cannot withstand the melting temperature of metals.

In the smelting process of metal, we will need to rapidly heat up according to the needs of the process, or to quickly cool down, that is, whether the graphite crucible can withstand the rapid cooling. For example, when melting a copper alloy, the melting point of copper is 1083.4 degrees Celsius. When the temperature reaches the temperature, the copper metal melts, but according to the process requirements, it is required to rapidly cool down to a certain value, which places demands on the crucible. Graphite crucible belongs to the category of ceramic paper. Its properties are the same as those of ceramics and glass. It can't withstand the rapid cooling and hot, which will cause the crack of the crucible, and the serious situation will cause the burst.

It has strong corrosion resistance to acid and alkaline solutions and has excellent chemical stability. In the metallurgical, foundry, machinery, chemical and other industrial sectors, it is widely used in the smelting of alloy tool steel and the smelting of non-ferrous metals and their alloys, and has a good technical and economic effect.

There are two general production processes for graphite crucibles: plastic molding production processes and press molding production processes. The plastic molding process using clay as a binder has a long production cycle, high labor intensity, low work efficiency, and is burned with coal, which is highly polluted. However, due to the low investment, the process is mostly used in China; and the isostatic pressing equipment is used in the press forming process. Clean energy natural gas sintering, fundamentally solve the pollution problem, and reduce the production process by nearly 10, short cycle, high efficiency.