Graphite CAS 7782-42-5

Graphite CAS 7782-42-5

Introduction

Graphite, also known as black lead, is an allotrope of carbon with a relative density of 2.256 g/cm³. Graphite is opaque and greasy to the touch, with colors ranging from iron black to steel gray. Its forms can be crystalline, flake, scaly, streaky, or layered. Graphite has low hardness, is chemically stable, and is non-reactive with acids, alkalis, and other agents. It is resistant to high temperatures, corrosion, thermal shock, and radiation, possesses high strength and toughness, and exhibits physical and chemical properties such as self-lubrication and electrical and thermal conductivity. 

It is widely used in metallurgy, machinery, electronics, military, defense, aerospace, and other fields. Large-scale graphite exhibits superior lubrication, wear resistance, electrical and thermal conductivity, and anti-permeation properties, playing a key role in high-end lubrication, sealing, and large-scale integrated circuits. 

Graphite can be extracted from graphite deposits or manufactured through a series of processing steps using raw materials such as petroleum coke and pitch coke.  Graphite can be used as an anti-wear agent and lubricant. High-purity graphite is also used as a neutron moderator in atomic reactors. In addition, this type of material can also be used to manufacture crucibles, electrodes, brushes, dry batteries, graphite fibers, heat exchangers, coolers, arc furnaces, arc lamps, pencil refills, etc.

Specification

Application

Graphite can be used to produce refractory materials, conductive materials, wear-resistant materials, lubricants, high-temperature resistant sealing materials, corrosion-resistant materials, thermal insulation materials, adsorption materials, friction materials and radiation protection materials, etc. These materials are widely used in metallurgy, petrochemical industry, machinery industry, electronics industry, nuclear industry and national defense. 

 Refractory materials 

In the steel industry, graphite refractory materials are used for refractory linings of arc blast furnaces and oxygen converters, refractory linings of ladles, etc.; graphite refractory materials are mainly integral casting materials, magnesia carbon bricks and aluminum graphite refractory materials. Graphite is also used in powder metallurgy and metal casting film forming materials. Graphite powder is added to molten steel to increase the carbon content of steel, giving high carbon steel many excellent properties. 

 Conductive materials are used in the electrical industry to manufacture electrodes, brushes, carbon rods, carbon tubes, positive electrodes of mercury rectifiers, graphite gaskets, telephone parts, coatings for television picture tubes, etc. 

Wear-resistant lubricating materials

 Graphite is often used as a lubricant in the machinery industry.  Lubricating oil cannot be used under high speed, high temperature and high pressure conditions, while graphite wear-resistant materials can work at high sliding speeds at temperatures of 200-2000 ℃ without lubricating oil. Many equipment that transport corrosive media widely use graphite materials to make piston cups, seals and bearings, which do not require lubricating oil when running. Graphite emulsion is also a good lubricant for many metal processing (wire drawing, tube drawing). 

Graphite that has been specially processed by corrosion-resistant materials has the characteristics of corrosion resistance, good thermal conductivity and low permeability. It is widely used in the production of heat exchangers, reaction tanks, condensers, combustion towers, absorption towers, coolers, heaters, filters, and pump equipment. It is widely used in petrochemical, hydrometallurgy, acid and alkali production, synthetic fibers, papermaking and other industrial sectors, which can save a lot of metal materials. 

 High-temperature metallurgical materials 

can be used as glassware casting molds because graphite has a small thermal expansion coefficient and can withstand rapid cooling and heating changes. After using graphite, ferrous metal castings are obtained with precise dimensions, smooth surfaces, and high yield rates. They can be used without processing or with minimal processing, thus saving a lot of metal. In the production of cemented carbide and other powder metallurgy processes, graphite materials are usually used to make press molds and porcelain boats for sintering. Single crystal silicon crystal growth crucibles, regional refining containers, bracket fixtures, induction heaters, etc. are all made of high-purity graphite. In addition, graphite can also be used as graphite insulation boards and bases for vacuum smelting, high-temperature resistance furnace tubes and other components. 

 Atomic energy and defense industry 

Graphite has good neutron moderator properties and is used in atomic reactors. Uranium-graphite reactors are currently the most widely used atomic reactors. The moderator material in atomic reactors used for power should have high melting point, stability, and corrosion resistance. Graphite can fully 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 0.5 ppm. In the defense industry, graphite is also used to manufacture nozzles for solid fuel rockets, nose cones for missiles, parts for space navigation equipment, thermal insulation materials and radiation-proof materials. 

(1) Graphite can also prevent boiler scaling. Tests conducted by relevant units have shown that adding a certain amount of graphite powder to water (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 pipelines to prevent corrosion and rust. 

(2) Graphite has gradually replaced copper as the preferred material for EDM electrodes. 

(3) Graphite deep-processing products are added to plastic products and rubber products to prevent them from generating static electricity. Many industrial products need to have anti-static and electromagnetic radiation shielding functions. Graphite products have both of these functions. The application of graphite in plastic products, rubber products and other related industrial products will also increase. 

In addition, graphite is also used as a polishing agent and rust preventive for glass and papermaking in light industry. It is an indispensable raw material for the manufacture of pencils, ink, black paint, printing ink, and artificial diamonds. It is a very good energy-saving and environmentally friendly material. The United States has used it as a car battery. With the development of modern science and technology and industry, the application field of graphite is constantly 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.