amorphous graphite, Natural graphite powder

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Amorphous Graphite descriptions
Amorphous graphite is the least valuable but most abundant form of graphite and makes up around *0% of the graphite market. Amorphous graphite is a seam mineral and is typically higher in ash than other forms of natural graphite. As it is often associated with and formed within coal seams which are not graphitic, Amorphous graphite is difficult to separate from the coal and usually results in a lower quality and lower priced product. Amorphous graphite contains ****0% carbon and is used in many lubricant products especially greases, forging lubricants, etc. In applications where higher ash content is acceptable or preferred, Amorphous graphite is a good choice.
Graphiteis an important industrial mineral. Graphite is an excellent conductor of heat and electricity, and has the highest natural strength and stiffness of any material. At the same time, graphite is one of the lightest of all reinforcing agents and has high natural lubricity, making it especially valuable to the steel and automotive industries.
Graphiteexhibits the properties of a metal and a nonmetal, which makes graphitesuitable for many industrial applications. The metallic properties include thermal and electrical conductivity. The nonmetallic properties include inertness, high thermal resistance, and lubricity. The combination of conductivity and high thermal stability allows graphite to be used in many applications such as refractories, batteries, and fuel cells. Lubricityand thermal conductivity make graphitean excellent material for high-temperature applications, because it results in a material that provides effective lubrication at a friction interface while furnishing a thermally conductive matrix to remove heat from the same interface. Lubricity and electrical conductivity allow its use as the primary material in the manufacture of brushes for electric motors. A graphite cabon brush effectively transfers electric current to a rotating armature while the natural lubricity of the brush minimizes frictional wear.
 
 
Steelmaking
In steelmaking, natural graphite is used as an agent to increase the carbon content of steel.
The largest use of natural graphite is in the manufacturing of steel for refractory products due to its high melting point, thermal conductivity, and low reactivity. Natural graphite in this end use mostly goes into carbon raising in molten steel, although it can be used to lubricate the dies used to extrude hot steel. Supplying carbon raisers is very competitive, therefore subject to cut-throat pricing from alternatives such as synthetic graphite powder, petroleum coke, and other forms of carbon. A carbon raiser is added to increase the carbon content of the steel to the specified level.
 
The electrodes used in many electrical metallurgical furnaces, including the electric arc furnaces used in steel processing, are manufactured from graphite. In the production of steel itself, graphite is used as a carbon raiser to strengthen steel. Its also used in blast furnace linings for the production of iron because of its high thermal conductivity.
 
Refractory Materials
Refractories remain the largest end use for the graphitemarket (*5%), where flake and amorphous grades are used in various applications。
Amorphous graphite is used in the refractories industry.Due to its high temperature stability and chemical inertness graphite is a good candidate for a refractory material. It is used in the production of refractory bricks and in the production of “Mag-carbon” refractory bricks (Mg-C.) Graphite is also used to manufacture crucibles, ladles and moulds for containing molten metals. Additionally graphite is one of the most common materials used in the production of functional refractories for the continuous casting of steel. In this application graphite flake is mixed with alumina and zirconia and then isostatically pressed to form components such as stopper rods, subentry nozzles and ladle shrouds used in both regulating flow of molten steel and protecting against oxidation. This type of material may also be used as shielding for pyrometers.
 
In the production of iron, graphite blocksare used to form part of the lining of the blast furnace. Its structural strength at temperature, thermal shock resistance, high thermal conductivity, low thermal expansion and good chemical resistance are of paramount importance in this application. 
 
 
Crucibles
Graphitecrucibles are used for melting aluminum, brass and other non-ferrous metals. These crucibles are produced by mixing graphite, sand and clay together and pressing it on the article at a high temperature. Flake and crystalline forms of graphite are the most used in manufacturing of crucibles. Crucibles began using very large graphite, and carbon-magnesite brick requiring not quite so large flake graphite; for these and others there is now much more flexibility in size of flake required, and amorphous graphite is no longer restricted to low-end refractories
 
Foundry coating
Amorphous graphite or fine flake graphite  can be added to water‐based paint in order to create a foundry facing mold wash.By painting the inside of a mold with this wash, then leaving it to dry, a fine graphite coat is made that is able to ease the separation of an object cast after hot metal has cooled
A foundry facing mold wash is a water-based paint of amorphousor fine flake graphite. Painting the inside of a mold with it and letting it dry leaves a fine graphite coat that will ease separation of the object cast after the hot metal has cooled. Graphite lubricants are specialty items for use at very high or very low temperatures, as forging die lubricant, an antiseize agent, a gear lubricant for mining machinery, and to lubricate locks. Having low-grit graphite, or even better no-grit graphite (ultra high purity), is highly desirable. It can be used as a dry powder, in water or oil, or as colloidal graphite (a permanent suspension in a liquid). An estimate based on graphite consumptionstatistics indicates that 3,**0 tonnes was used in this fashion in ***2.
 
 
Carbon brushes Electrical ApplicationsThe main application for amorphous graphite as an electrical material is in the manufacture of carbon brushes in electric motors. In this application the performance and lifetime of the component is very dependent on grade and structure.
It is made from the carbon black, graphite, coke and a variety of carbon powder materials. After about ***0 ℃ high temperature processing, the various carbon materials become microcrystalline artificial graphite. It has excellent self-lubricating properties and, less wear on the commutator. It is widely used in various types of AC and DC motor .
 
 
Lithium‐ion/Alkaline Batteries
Mobile energy markets, currently the second largest consumer of graphite (*5%), are also showing promising growth over the short and longer term. Graphite is used in the electrodes of a number of battery types including Li-ion, where it is intercalated with lithium ions - creating a very stable battery that provides a high energy density.
Lithium-ion battery with high specific energy, high voltage, long cycle life, self-discharge rate, no －memory effect and environment-friendly, etc., has been widely used as a portable electronic devices and electric vehicles energy. Most portable devices such as mobile phones, laptops, mp3 players or digital cameras use lithium‐ion batteries. The evolution of electric vehicles, including hybrid electric vehicles and plug in electric vehicles has changed this the result is rapidly growing demand for lithium‐ion batteries. High‐purity large‐flake graphite is essential for the production of these batteries. There is *0 to *0 times more graphitewithin a lithium‐ion battery than lithium. This is because graphite is the preferred anode material for most battery designs, as the anode requires a carbon material that is porous. An average hybrid electric vehicle requires over *0 kg of graphite, while an average electric vehicle requires *0 kg..
 
Conductive coating
Good conductive coating is made of dispersed conductive graphite coated particles. It can provide excellent static conductivity and a energy absorbing protection layer. It also provides good covering protective properties. Coating with water-based and solvent, and can be applied in the aluminum, copper, stainless steel, aluminum and titanium bipolar plate.
Now battery positive plate and negative electrode sheet were using a conductive coating. It has some main advantages. 1) protection of collector, and improve battery life cycles, so the energy storage battery can be widely used; 2) to improve the active material and the electric pole piece contacts, to improve adhesion; 3) increase the specific surface area, to improve the resistance, in particular, high-power battery; 4) to improve the battery performance rate.
Conductive coating has a broad future development scenarios, and now many American lithium battery manufacturers are using this technology.
 
Lubricants
High grade graphite in amorphous and crystalline form, having the ability to remain suspended in oil, is used in the manufacturing of lubricants. Irrespective of the working condition, graphite shows very low friction which is why it is used in lubricants. It keeps the moving surface cool and minimizes the friction. Graphite lubricants are specialty items for use at very high or very low temperatures, as forging die lubricant, an antiseize agent, a gear lubricant for mining machinery, and to lubricate locks.
 
Brake linings, Gaskets and Clutch Materials
Amorphous graphite can be used in brake linings, gaskets and clutch materials as it is now a widespread replacement for asbestos in many automotive functions. If fuel cells begin replacing internal combustion engines as experts predict, then amorphous graphite will likely be in very high demand in the automotive industry.
Natural amorphous and fine flake graphite are used in brake linings or brake-shoes for heavier (nonautomotive) vehicles, and became important with the need to substitute for asbestos. This use has been important for quite some time, but nonasbestos organic (NAO) compositions are beginning to cost graphite market share. A brake-lining industry shake-out with some plant closings has not helped either, nor has an indifferent automotive market.
 
Pencils
Pencils, one of the oldest uses of graphite, make use of the weakly bonded graphite layers brushing off on contact with surfaces and leaving a residue.
Pencil lead is most commonly a mix of powdered graphite and clay; it was invented by Nicolas-Jacques Conté  in ***5.
Graphite in amorphous form is used in the manufacturing of lead used in pencils. Amorphous graphite is preferred as it leaves a dark streak on paper. More fine the powder, darker the smear. In case the graphite is highly flaky, the smear loses its darkness.
Today, pencils are still a small but significant market for natural graphite. Around 7% of the 1.1 million tonnes produced in ***2 was used to make pencils. Low-quality amorphous graphite is used and sourced mainly from China.
 
Other uses
Paiting
Amorphous graphiteis mainly used as a lubricant additive, as a pigment in paints; in plastic refractories, and in other applications where additions of graphite improve the process or the end product.
One of the common uses of graphite is in manufacturing of pencils and paints. In production of paints, powdered form of lump graphite is used and since graphiteis a natural water repellent. Graphite is the best choice for giving a protective coating on wood.