Several major advantages of high-purity graphite products

Graphite with a purity of over 99.9% is called high-purity graphite. It is ideal for use in inorganic non-metallic crucibles, single crystal furnace heaters, electric spark machining graphite, sintering molds, metal coating and plating, and graphite crucibles for semiconductor technology. High-purity graphite, which has undergone special processing, features corrosion resistance, good thermal conductivity, and low permeability.

Several major advantages of high-purity graphite products:

(1) High-temperature resistance: Graphite has a melting point of 385+-℃ and a boiling point of 4250℃. Even when subjected to high-temperature arc burning, the loss in weight is minimal, and the coefficient of thermal expansion is also very small. The strength of graphite increases with temperature, and at 2000℃, the strength of graphite increases by a certain multiple. During exothermic welding construction, the temperature of the chemical reaction caused by igniting the exothermic welding flux is very high, which requires the materials used in the exothermic welding mold to be high-temperature resistant.

(2) Electrical and thermal conductivity: The electrical conductivity of high-purity graphite is 100 times higher than that of general non-metallic minerals. Its thermal conductivity exceeds that of metals such as steel, iron, and lead. The thermal conductivity coefficient decreases with increasing temperature, and even at higher temperatures, graphite becomes an insulator. Graphite can conduct electricity because each carbon atom in graphite forms only three covalent bonds with other carbon atoms, while still retaining one free electron to transmit charge. During exothermic welding construction, many points often need to be welded, and the construction is also large. Graphite's thermal conductivity can meet this requirement, as it can withstand high temperatures and quickly cool down.

(3) Lubricity: The lubricating performance of high-purity graphite depends on the size of the graphite flakes. The larger the flakes, the lower the friction coefficient, and the better the lubricating performance.

(4) Chemical stability: Graphite exhibits good chemical stability at room temperature and is resistant to corrosion by acids, alkalis, and organic solvents.

(5) Malleability: High-purity graphite exhibits excellent toughness and can be rolled into very thin sheets. Exothermic welding sometimes requires molds for various joint forms. The malleability of high-purity graphite allows for the fabrication of exothermic welding molds in different models, specifications, and connection forms.

(6) Thermal shock resistance: High-purity graphite can withstand drastic temperature changes without being damaged when used at room temperature. During sudden temperature changes, the volume of graphite does not change significantly, and no cracks will occur.