Graphite soft, black gray, greasy, can pollute the paper. The hardness is 1 ~ 2, along the vertical direction with the increase of impurities the hardness can be increased to 3 ~ 5. The specific gravity is 1.9 to 2.3. The specific surface area is concentrated in the range of 1-20m2/g. Under the condition of isolation of oxygen, its melting point is above 3000℃, which is one of the most temperature-resistant minerals. It conducts electricity and heat.
Graphite can be used in the production of refractory materials, conductive materials, wear resistant materials, lubricants, high temperature resistant sealing materials, corrosion resistant materials, heat insulation materials, adsorption materials, friction materials and radiation protection materials, etc., these materials are widely used in metallurgy, petrochemical, machinery industry, electronics industry and so on.
Fire resistant material
In iron and steel industry, graphite refractories are used in arc blast furnace and oxygen converter refractory lining, ladle refractory lining, etc. Graphite refractories are mainly integral casting materials, magnesium-carbon bricks and aluminum-graphite refractories. Graphite is also used in powder metallurgy and metal casting film material, graphite powder added to molten steel to increase the carbon content of steel, so that high carbon steel has many excellent properties.
Used in the electrical industry for the manufacture of electrodes, brushes, carbon rods, carbon tubes, mercury positives, graphite washers, telephone parts, TV picture tube coating.
Wear resistant lubricating material
Graphite is often used as a lubricant in the machinery industry. Lubricating oil often can not be used in high speed, high temperature, high pressure conditions, and graphite wear-resistant materials can be in the temperature of -200 ~ 2000℃ at a very high sliding speed, without lubricating oil work. Many corrosive media conveying equipment, widely used graphite material made of piston cups, seals and bearings, they do not need to add lubricating oil when running. Graphite is also a good lubricant for many metal processing (wire drawing, tube drawing).
Corrosion resistant material
After special processing of graphite, with corrosion resistance, good thermal conductivity, low permeability, it is widely used in the production of heat exchanger, reaction tank, condenser, combustion tower, absorption tower, cooler, heater, filter, pump equipment. Widely used in petrochemical industry, hydrometallurgy, acid and base production, synthetic fiber, paper and other industrial sectors, can save a lot of metal materials.
High temperature metallurgical material
Due to the small coefficient of thermal expansion of graphite, and the ability to change cold and hot, can be used as a glass casting mold, the use of graphite after the black metal casting size is accurate, the surface is smooth, high yield, can be used without processing or slightly processing, thus saving a lot of metal. The production of hard alloy and other powder metallurgy process, usually made of graphite materials for pressing and sintering of porcelain boats. Monocrystalline silicon crystal growth crucible, area refining vessel, bracket fixture, induction heater and so on are processed with high purity graphite. In addition, graphite can also be used for vacuum smelting graphite heat insulation plate and base, high temperature resistance furnace tube and other components.