The glassy carbon (GC) is a new type of carbon material ,it’s similar to glass and in the carbon structure, and it is also a new type of amorphous carbon structure material. The GC is made of biological resin carbon through high temperature pyrolyzation and carbonization . It does not contain harmful substances on the human body, high purity carbon. Glassy carbon is characterized by its high hardness and permeability due to its port morphology and structural characteristics similar to that of glass.

　　Glass carbon has high strength, hardness and elastic modulus. It can be used to make high speed typewriter wheel and record. Glass carbon has many superior properties: density is small, about 1.3g/cm3; 3800℃high temperature resistance; anti penetration; corrosion resistance. It’s widely used in chemical industry, metallurgical industry, electronic industry, biological engineering and many other fields.

　　Glass carbon can withstand 1 million 300 thousand times the atmospheric pressure, in other directions it can withstand the atmospheric pressure of 600 thousand times. It’s used in the manufacture of ultra high temperature micro electrode used as stoichiometric electrode, its diameter is below 1mm, a disc type, cylindrical, conical, used as a chemical measurement electrode used in analysis of trace components and measurement of various compounds coexisting clinical specimens, samples and raw thick liquid etc.. It can be used in medical equipment production such as tooth material and cardiac pacemaker. Glass carbon can be used for 3800 degrees heat insulation material and high heat resistant protective clothing. special glass carbon ultra high temperature crucible, ultra high temperature beaker, ultra high temperature pipe, ultra high temperature casting mold, carbon crystal wall heating, the carbon crystal heating plate, ultra high temperature electric heater, glass carbon fiber composite panel for the touch screen of computer and mobile phone , it’s also used in the manufacture of high-speed wheel typewriter and recording.

　　According to the quality requirements of products, the selection of raw materials and process conditions, the cathode carbon blocks in China are divided into 3 categories: common cathode carbon block, semi graphite carbon block and graphite carbon block. Ordinary cathode carbon block with 1250 to 1350 degrees Celsius calcined anthracite as the main raw material. Semi graphite carbon block according to the production process is divided into two different.

　　Which is a kind of high quality high temperature calcined anthracite or graphite fragments more even with all the bits of graphite as aggregate, green products after forming only after calcination (calcination temperature less than 1200 DEG C) is no longer in the graphite furnace heat treatment, the carbon block called semi graphite carbon block.

　　Another with more easily to the graphite of the coke for aggregate, raw material after baking and then enter the graphite furnace in 1800 to 2000 degrees Celsius temperature for heat treatment, this kind of carbon block called semi graphite (chemical) carbon block. The strength and hardness of the former is higher, and the conductivity of the latter is better. Graphite carbon block, in order to ease the graphite coke as raw material, the temperature of its graphite processing should reach about 2500.

　　The difference between the semi - graphite carbon block and the graphite carbon block lies in the degree of the ordered arrangement of the products, which is different from the degree of the degree of. The size of the product can be used to indicate the extent of the degree of graphite. The crystal lattice of the graphite carbon block is basically in a state of orderly arrangement, and the resistivity is less than 15 mu m; the degree of the semi graphite carbon block is low or only partially, and the resistivity is 15 to 45 m. In the process, the heat treatment temperature, the heat treatment of the semi graphite carbon block is about 2000 degrees Celsius, and the temperature of the graphite carbon block is 2800 to 2500 degrees Celsius. Common cathode carbon block, the resistivity of 50 ~ 60 mu m. Graphite cathode carbon block China has not been applied.

　　The expandable graphite was first discovered by the German scientist Shafautl when he immersed the graphite into concentrated sulfuric acid and nitric acid in 1841. But until the year of 1963, The Union Carbide Company in the United States first applied the patent of preparation of sealing material by the expansion graphite, and it was real used in the industrial production in the beginning of 1968 . Later, Countries in the world have launched the expansion of graphite research and development, and get serious scientific research and results, so in the current , the expansion graphite has become a kind of very important function of graphite materials.

　　The expandable graphite can be rapid expansion, expansion ratio of up to several tens to hundreds of even thousands of times under high temperature heating , the apparent volume of expanded graphite was 250 ~ 300mL/g or more, the graphite after expansion is wormlike, its size between a few tenths of millimeters to a few millimeters, with a large number of unique network like porous structure in the interior, called expanded graphite or graphite worm, the expanded graphite has many special properties.

　　The expandable graphite can be used in iron and steel, metallurgy, petroleum, chemical engineering, aerospace, atomic energy and other industrial sectors, its application fields are very widely. For example, the expandable graphite can be used as a flame retardant, and is used for fireproof plastic products, fire retardant composite materials and products;

　　The expandable graphite can be used as a multi band stealth smoke agent and shielding materials, it’s widely used in the military field. The flexible graphite products which is made of expanded graphite was known as the "seal of the king." it plays an important role in the field of mechanical seal, fireproof material; the expanded graphite can be used as a sorbent material for recycling of waste and wastewater treatment as the microbial carrier in the field of environmental protection.

　　Steelmaking using carburizing agent and cast iron using carburizing agent, and some other materials are also useful for adding to the carburizing agent, such as brake pads with additive, friction material. Recarburizer belongs to external steel and iron carbon materials. High quality carburizing agent additive is essential for production of high quality steel.

　　Carburizing agent, there are many kinds of raw materials, production processes are different, wood carbon, carbon coal, coke, graphite, etc., in which various categories and a lot of small type. High quality carburizing agent generally refers to after graphite carburant, in under the condition of high temperature and carbon atoms arranged in graphite morphology, so called for graphitization. Graphite can reduce the content of impurities in the carburant carburant, increasing carbon content, reducing sulfur content.

　　Carbon in cast use, can greatly increase the amount of scrap, reduce the amount of pig iron or no iron. Smelting furnace cast materials, should be the carburant with scrap charge together to put in, small doses of add can choose to add on the surface of the molten iron. But to avoid large quantities of hot metal in to feed, to prevent excessive oxidation and carbonization effect is not obvious and the carbon content of the casting is not enough. Increase the quantity of carbon agent, according to the ratio of other raw materials and carbon content to be. Different types of cast iron, according to need to choose different types of recarburizer. Carburant characteristics choose pure carbon graphite material, reduce too much impurity in the iron, carburizing agent choose appropriate casting production cost can be reduced.

　　Use of carbon

　　In the smelting process, due to the ingredients or improper loading and decarbonization excess and other reasons, sometimes resulting in steel carbon content did not reach the top of the requirements, then to the carburization of molten steel. Recarburizer used a carbon electrode, iron powder, petroleum coke powder, charcoal powder and coke powder. Smelting, high carbon steel, containing less impurities in oil Jiaozuo carburetant. The top blown converter steelmaking carburant is high fixed carbon, ash, volatile matter, sulfur, phosphorus and nitrogen impurity content is low, and dry, clean, moderate granularity

　　In July 2012, scientists at the Keel University and the University of Hamburg, Germany, developed the Flying graphite

　　The world's lightest material "flying graphite" (Aero graphite), its density is only 0.2 mg / cubic centimeter, replaced the air gel became the world's lightest material. Looks like a black opaque sponge, made up of 99.99% air.

　　This new material has a stable performance, good electrical conductivity, ductility and very strong. It is composed of a porous carbon annotate in the nanometer and micron scale, which is composed of a mesh structure. Although its quality is very light, but the flexibility is very good, has a strong anti compression capacity and tension load. It can be compressed to 95%, and then restored to the original size. It can absorb almost all the light.

　　Advantage

　　1, stable performance;

　　2, with good electrical conductivity;

　　3, strong extension

　　4, very stable

　　Purpose

　　1. Flying graphite is mounted on the electrode of lithium ion battery, the battery need electrolyte solution becomes less and less, battery quality thus greatly reduced, small cell can be used in electric car or bike.

　　2 can make the composite material with electrical conductivity, so as to avoid electrostatic interference.

　　3 can also be applied to the electronic equipment used in the aerospace and satellite fields, because these devices must be able to withstand a large number of vibration.

　　4 is expected to be used in water purification, as an adsorbent for the adsorption of pollutants in water, because it can oxidize or decompose and remove pollutants in water.

　　5 can be used in the constant temperature box or ventilation equipment to purify the environment air.

　　Beijing Great Wall Co., ltd is a leading company of graphite product. We always offer the best quality and the competitive price for our customer. We are looking forward to your enquiry and cooperation in the future.

　　Carbon carbon composite material is a new type of high temperature material, with light weight, high modulus, high specific strength, low thermal expansion coefficient, high temperature resistance, heat shock resistance, corrosion resistance, good vibration absorption and so on.

　　In the application, as an anti ablation, short time use of the material, carbon carbon composites have been successfully applied in the aerospace industry, such as rocket engine exhaust nozzle, throat lining, aerospace aircraft wing leading edge and so on. In the field of aerospace applications, the most successful example when the number of carbon carbon composite material brake disc, in this area has formed a mature market.

　　Carbon carbon composite brake disk advantages mainly due to its own density, high temperature resistant characteristics, because its density is small, the use of carbon / carbon disk and can greatly reduce the weight of each aircraft. An aircraft brake friction caused by the temperature rise of more than 500, at this time, the high temperature resistance of carbon carbon material shows great superiority.

　　In order to solve the oxidation of carbon / carbon materials, the effects of matrix modification on the oxidation resistance of SiO2, ZrO2, Al2O3 and so on.

　　Carbon carbon composite material is not used for rotating parts of the engine yet, the reason is mainly antioxidant problem, the traditional design will not be suitable for carbon carbon composite materials, must be based on the characteristics of the material to carry out a special, new structural design.

　　The application prospect of carbon carbon composites is very attractive, but it is still dependent on a series of key problems to solve the key components of the aircraft engine.V

Carbon carbon composite material is made of reinforcing carbon fiber and carbon matrix,the C/C composite material need presoma decompose into matrix carbon,the property of the carbon decide that it can not be made by the inorganic material and metal matrix composite material.

　　The preparation method mainly divided into three steps: prefabricate the carbon fiber embryo then increase the carbon content and density of the matrix and the last one is high temperature heating(graphitization).

　　1、According to the different requirement and different production,the way to make the carbon fiber embryo mainly have:

　　1) Short fiber molding,

　　2) Long fiber weaving and lamination,

　　3) Multidimensional weaving or puncturing.

　　4) Novoltex 3D fine woven fabric.

　　2、There are three methods to increase the carbon content and density of the matrix:

　　1) Liquid phase method

　　thermosetting resin or thermoplasticity pitch impregnation and carbonization method.

　　2) Chemical vapor phase method

　　Mainly refers to Chemical Vapor Infiltration(CVI)

　　3) Combination of the two methods.

　　3、high temperature treatment

　　The temperature of carbon carbon composite material usually range from 2400℃~3000℃,the purpose is to promote the formation of graphite structure,so it also called the graphitization.after the graphitization,the thermal conductivity of carbon carbon composite material can increase from 10W/(m.k) to 120W/(m.k),but at the same time ,the mechanical property will reduce about 10%.

Carbon fiber is one kind of special fiber consists of carbon element.it has high temperature resistant,good wear resistance,electrical conductivity,thermal conductivity,corrosion resistance etc.It’s fiber in shape,flexible,and could be machined into fabric.

Along the fiber axis direction,it has a high strength and modulus.density of the carbon fiber is low,so it has a high specific strength and specific modulus.

The most important use of carbon fiber is to be the reinforce which be manufactured as advanced composite materials with resin,metal,ceramic and carbon etc.

The carbonization processing of the precursor fiber,the raw material,carbon content below:

precursor fiber

The procedure of the 3 process above includes:

1. stabilizing treatment(200~400℃)
2. carbonization treatment(400~1400℃)
3. graphitization treatment(>1800℃)

In order to improve the bonding performance between carbon fiber and composite material,the surface treatment,sizing and drying are usually used. Another way to manufacture the carbon fiber is The vapor phase growth method. Under 1000℃,the mixed gas of methane and hydrogen with catalyzer could meet discontinuous and chopped carbon fiber,the max length is about 50cm. The structure of chopped carbon fiber is different from PAN or PITCH ones,it has an easy graphitization,good conductivity property etc.