The main purpose:
1. As refractory material: Graphite and its products have the properties of high temperature resistance and high strength. It is mainly used to make graphite crucibles in the metallurgical industry. Graphite is commonly used as a protective agent for steel ingots in steelmaking and the lining of metallurgical furnaces.
2, as a conductive material: used in the electrical industry to manufacture electrodes, brushes, carbon rods, carbon tubes, positive electrodes for mercury positive current, graphite gaskets, telephone parts, coatings for television picture tubes, etc.
3. As a wear-resistant lubricating material: Graphite is often used as a lubricant in the machinery industry. Lubricants often cannot be used under high-speed, high-temperature, and high-pressure conditions, and graphite wear-resistant materials can work at high sliding speeds in the temperature range of 200 ~ 2000 ℃ without lubricant. Many equipments for transporting corrosive media widely use graphite materials to make piston cups, seals and bearings. They do not need to be added with lubricant when running. Graphite milk is also a good lubricant for many metal processing (drawing, drawing).
4. Graphite has good chemical stability. Specially processed graphite has the characteristics of corrosion resistance, good thermal conductivity, and low permeability. It is widely used in the manufacture of heat exchangers, reaction tanks, condensers, combustion towers, absorption towers, coolers, heaters, and filters. , Pump equipment. Widely used in petrochemical, wet metallurgy, acid and alkali production, synthetic fiber, papermaking and other industrial sectors, can save a lot of metal materials.
5. For casting, sand turning, compression molding and high-temperature metallurgical materials: Because graphite has a small thermal expansion coefficient and can withstand rapid and rapid changes, it can be used as a mold for glassware. After graphite is used, ferrous metal can obtain accurate casting dimensions and smooth surface finish. High, can be used without machining or a little processing, thus saving a lot of metal. Production of powder metallurgy processes such as cemented carbide, graphite materials are usually used to make stampers and porcelain boats for sintering. Crystal growth crucibles for single crystal silicon, regional refining vessels, holder fixtures, induction heaters, etc. are all processed with high-purity graphite. In addition, graphite can also be used for vacuum smelting of graphite heat insulation plates and bases, high-temperature resistance furnace tubes, rods, plates, grids and other components.
6. Used in atomic energy industry and national defense industry: Graphite has a good neutron moderator used in atomic reactors. Uranium-graphite reactor is one of the most widely used atomic reactors. As a deceleration material in a nuclear power reactor for power, it should have high melting point, stability, and corrosion resistance. Graphite can completely meet the above requirements. The purity of graphite used in atomic reactors is very high, and the impurity content should not exceed tens of PPM. In particular, the boron content should be less than 0.5PPM. In the defense industry, graphite is also used to make nozzles for solid fuel rockets, nose cones for missiles, parts for space navigation equipment, thermal insulation materials and anti-ray materials.
7. Graphite can also prevent boiler scaling. Unit tests have shown that adding a certain amount of graphite powder (about 4 to 5 grams per ton of water) can prevent scaling on the boiler surface. In addition, graphite can be applied to metal chimneys, roofs, bridges and pipes to prevent corrosion and rust.
8. Graphite can be used as pencil lead, pigment and polishing agent. After special processing of graphite, various special materials can be made for the relevant industrial sectors.
In addition, graphite is also a polishing agent and rust inhibitor for glass and paper in the light industry. It is an indispensable raw material for the manufacture of pencils, inks, black paints, inks and artificial diamonds and diamonds. It is a very good energy-saving and environmental-friendly material, and it has been used as a car battery in the United States. With the development of modern science and technology and industry, the application field of graphite is still expanding. It has become an important raw material for new composite materials in the high-tech field and plays an important role in the national economy.