dvd无码视频在线观看|日韩欧美人妻视频|天天爽首页永久入口18岁|亚洲国产精品VA免费

Graphite can be used to produce refractories, 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 industry, machinery industry, electronics industry, nuclear industry and national defense, etc.

Refractories

In the iron and steel industry, graphite refractories are used for the lining of electric arc furnace and oxygen converter, the lining of ladle, etc.; graphite refractories are mainly monolithic casting materials, magnesia carbon brick and aluminum graphite refractories. Graphite is also used in powder metallurgy and metal casting as film-forming materials. The addition of graphite powder to molten steel increases the carbon content of steel, which makes high carbon steel have many excellent properties.

Conductive material

In the electrical industry, it is used as the anode of electrode, brush, carbon rod, carbon tube, mercury positive current device, graphite washer, telephone parts, TV picture tube coating, etc.

Wear resistant lubricating material

Graphite is often used as a lubricant in the mechanical industry. The lubricating oil can not be used under the condition of high speed, high temperature and high pressure, while the graphite wear-resistant material can work without lubricating oil at a very high sliding speed in the temperature of - 200 ~ 2000 ℃. Many equipment for transporting corrosive media are widely made of graphite materials, such as piston cup, seal ring and bearing. They do not need to be added with lubricating oil when they are running. Graphite emulsion is also a good lubricant for many metal processing (wire drawing, tube drawing).

Corrosion resistant material

After special processing, graphite has the characteristics of corrosion resistance, good thermal conductivity and low permeability, so it is widely used to make heat exchanger, reaction tank, condenser, combustion tower, absorption tower, cooler, heater, filter and pump equipment. Widely used in petrochemical, hydrometallurgy, acid and alkali production, synthetic fiber, paper and other industrial sectors, can save a lot of metal materials.

High temperature metallurgical materials

Due to the small coefficient of thermal expansion of graphite and its ability to withstand the changes of rapid cooling and heat, it can be used as a mold for glassware. After using graphite, the ferrous metal can obtain the accurate size of the casting, and the surface finish yield is high. It can be used without processing or a little processing, so a large number of metals are saved. In the production of cemented carbide and other powder metallurgy processes, graphite materials are usually used to make ceramic boats for pressing and sintering. Crystal growth crucibles, regional refining vessels, bracket clamps, induction heaters, etc. of monocrystalline silicon are all made of high-purity graphite. In addition, graphite can also be used as heat shield and base of vacuum smelting, high temperature resistance furnace tube and other components.

Atomic energy and national defense industry

Graphite has a good neutron retarder used in atomic reactor. Uranium graphite reactor is one of the most widely used nuclear reactors. The decelerating materials used in nuclear power reactors should have the properties of high melting point, stability and corrosion resistance. Graphite can fully meet the above requirements. The purity of graphite used as an atomic reactor is very high, and the impurity content should not exceed dozens of ppm. In particular, the boron content shall be less than 0.5ppm. In the national defense industry, graphite is also used to make nozzles of solid fuel rockets, nose cones of missiles, parts of space navigation equipment, heat insulation materials and anti radiation materials.

(1) Graphite can also prevent the boiler from scaling. The relevant unit test shows that adding a certain amount of graphite powder (about 4-5g per ton of water) to the water can prevent the boiler from scaling. In addition, graphite coating on metal chimneys, roofs, bridges and pipelines can prevent corrosion and rust.

(2) Graphite gradually replaced copper as the preferred material of EDM electrode.

(3) When graphite deep processing products are added to plastic products and rubber products, static electricity will not be generated in plastic products and rubber products. Many industrial products need to have anti-static and shielding electromagnetic radiation 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 a polishing agent and antirust agent for glass and paper in light industry, and an indispensable raw material for making pencils, ink, black paint, inks, artificial diamonds and diamonds. It is a good energy-saving and environmental protection material, which 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 of new composite materials in the high-tech field and plays an important role in the national economy.