Graphite blocks is the widely used graphite material and be used in many industies , from the material it can be divied into carbon blocks and graphite blocks , the difference is if the blocks is with the procedure of the graphitization . and for the graphite blocks , from the moulding method , it can be divided into three major kinds , isostatic graphite blocks , moulded graphite blocks and vibracation graphite blocks .

　　Graphite Blocks are widely used in the Tooling (EDM), Mould making (EDM), and General Manufacturing industries. We can make it up to 3600mm long and 850 wide and 850 tall. The blocks are available in various specifications and size are as per different construction applications. Characteristics of Graphite Blocks. Graphite Blocks features in high bulk density, low resistivity, oxidation resistance, corrosion resistance, high temperature resistance and good electrical conductivity, etc.

Special features:

• High purity
• fine grain
• good performance of electrical conductivity and thermal conductivity
• high density, good corrosion resistance, thermal shock resistance
• thermal stability
• high mechanical strength
• low permeability and good oxidation resistance

　　The raw material is capable of producing various semiconductor molds and radio tube.

　　Graphite blocks used for silicon carbide furnace, graphitization furnace and other metallurgical furnace, resistance furnace lining and conductive material, and the permeability of graphite heat exchangers.Widely used in electronics, metallurgy, chemical industry, steel and other fields, products of good quality, stable performance.

Solar battery and semiconductor wafer with graphite: photovoltaic industrial graphite materials: as a result of the isostatic pressing graphite materials have high strength, density, isotropic, made of graphite parts in use process heating, heating is even, at the same time due to the density of material evenly can effectively reduce material by thermal shock and produce the internal stress of thermal shock resistance (good), so it can greatly prolong the service life of equipment or instruments cycle, so in the semiconductor and solar industries, used the isostatic pressing graphite (isotropic graphite), making Cz type monocrystal pulling of graphite furnace thermal field components (crucible, heater and diversion tube, cover, etc.); Polycrystalline silicon smelting furnace heater,; Compound semiconductor manufacturing with heater, crucible, etc. Belongs to the high-quality goods of graphite materials, such as static pressure graphite with other ordinary graphite have excellent performance, is a hot field in polycrystalline silicon, monocrystalline silicon manufacturing refractory material of choice for basic materials. Fast development of solar photovoltaic power generation, nearly 10 years, the global solar photovoltaic industry average annual growth rate of 41.3% despite the economic crisis of 2009 attacks, too can industry remains more than 30% of global growth, after the Copenhagen climate BBS, will have a bigger development space, is expected to begin in 2010 will have an annual 50% ~ 60% of the global solar market grows.

　　China as the world's largest producer of solar photovoltaic (pv), whose share has reached 70% of the world, the consumption of industry in 2009 reached more than 5000 tons of high-grade graphite materials, are expected annual demand for isostatic pressing of graphite materials to increase at a speed of 25 ~ 30% on average, pv industry a huge demand for graphite monocrystalline silicon and polycrystalline silicon production, CFCCARBON will provide better products and services. The development of clean energy, the demand of the market and policy support, below is the most favorable conditions in the development of industry. Large size, high purity, high density, high strength, such as static pressure (isotropic) graphite materials are electronic and photovoltaic industry development needs, during the \"twelfth five-year\" will be the development of the isostatic pressing graphite manufacturing companies in China the best opportunity.

　　At present, the single crystal size to normalize development, a few years ago the prevailing 18-inch furnace 20-inch furnace quickly replaced in 2010 ~ 2011 years, and the bigger the trend of the development of the specification; Polysilicon is the large-scale development, in addition, polysilicon access rules is still under discussion, is the development direction of high-end products. Photovoltaic industry products of large-scale and high normalized, determines the has higher request to the graphite, i.e., more specifications, higher strength, higher purity.

  Graphite blocks is the widely used graphite material and be used in many industies , from the material it can be divied into carbon blocks and graphite blocks , the difference is if the blocks is with the procedure of the graphitization . and for the graphite blocks , from the moulding method , it can be divided into three major kinds , isostatic graphite blocks , moulded graphite blocks and vibracation graphite blocks .

　　Graphite Blocks are widely used in the Tooling (EDM), Mould making (EDM), and General Manufacturing industries. We can make it up to 3600mm long and 850 wide and 850 tall. The blocks are available in various specifications and size are as per different construction applications. Characteristics of Graphite Blocks. Graphite Blocks features in high bulk density, low resistivity, oxidation resistance, corrosion resistance, high temperature resistance and good electrical conductivity, etc.

　　Special features: High purity, fine grain, good performance of electrical conductivity and thermal conductivity, high density, good corrosion resistance, thermal shock resistance, thermal stability, high mechanical strength, low permeability, and good oxidation resistance

　　The raw material is capable of producing various semiconductor molds and radio tube.

　　Graphite blocks used for silicon carbide furnace, graphitization furnace and other metallurgical furnace, resistance furnace lining and conductive material, and the permeability of graphite heat exchangers.Widely used in electronics, metallurgy, chemical industry, steel and other fields, products of good quality, stable performance.

　　If you need graphite or carbon products , We interested in supplying those materials for you.As a leading Chinese graphite manufacturer and supplier, we specialize in providing high quality graphite material, carbon carbon composites and graphite parts.To buy graphite and carbon products please contact us and ask our sales manager for a quote.

　　Carbon/carbon composites is reinforced by carbon fiber and matrix carbon in two parts, according to the carbon fiber in the matrix form of carbon can be divided into the following three types:

　　The first: carbon fiber in the form of short fiber bundle randomly distributed in the matrix carbon.

　　The second: carbon fiber with continuous filament woven cloth, then composite laminated plates of forms exist in the matrix carbon.

　　The third: carbon fiber to between carbon cloth laminated plates and the transition between the two kinds of structure of 3 d braid structure, namely the form of a needled felt exist in the matrix carbon.

　　Carbon matrix according to its source and form can be divided into liquid phase method and gas phase method of two categories:

　　Such as liquid liquid phase method refers to use resin or asphalt. Carbon impregnated carbon fiber and solidification and carbonization, and organic matter removal of volatile organic matter composition, leaving the carbon composition, forming the matrix carbon composite material.

　　Gas phase method refers to the low molecular organic hydrocarbon through bake in a preheated in gas phase of carbon fiber reinforced body, and under the high temperature cracking and polymerization, forming the matrix carbon.

　　The distribution shape of carbon fiber reinforced, and the formation of the matrix carbon together, formed a variety of carbon/carbon composite material preparation pads, the actual use of the technology points of three categories:

　　The first category: short fibre moulded dipping carbonization process.

　　The process is first and foremost with resin impregnated carbon fiber filament formation of presoak belt, then cut short into a certain length of short fiber bundle, hot-pressing forming in the mold, after solidifying, carbonization treatment, reoccupy resin or pitch impregnation carbonization, and cycle times, until meet the requirements of material density. Finally after a certain processing to form carbon/carbon composites brake pads.

　　The process according to the coking pressure and other parameters can be divided into such as normal pressure, medium pressure and high pressure. The United States Honeywell and ABSC company mainly carbon brake was produced by the technology, its products are mainly applied in B767, MD11 aircraft, etc.

　　This process has the advantage of carbon fiber utilization ratio is high, the craft is simple, low production cost. The production of carbon/carbon composite material is isotropic state. Defect is low mechanical properties (see table 1), process in brake pad friction surface fracture phenomenon. The reason is for chopped carbon fiber reinforced body did not form a complete structure of the bundle. Another disadvantage is the wear rate is large, this is because the matrix carbon is ball, easy to form the abrasive abrasive wear.

　　The second category: carbon cloth laminated or needled felt precast body with chemical vapor deposition (CVD) process.

　　The process carbon fiber woven cloth first, then cut composite into prefabricated body or carbon fiber woven needle into needled felt kind of precast body, in the chemical vapor deposition in furnace using low molecular hydrocarbon deposits, until you reach the required density, finally after a certain processing to form carbon/carbon composites brake pads.

　　The process in the manner of precast body heat and air flow direction can be divided into isothermal constant pressure, differential pressure method, the temperature difference method, etc. Chinese bjgreatwall company can production

　　This process has the advantage of matrix carbon gradually grow along the carbon fiber surface and form, so closely matrix between carbon and carbon fiber structure. So the process of material mechanical properties of high (see chart 1). In addition, CVD carbon for the class of graphite layer structure, friction in the process of friction surface is easy to form a layer of graphite crystallite film, reduce material wear rate (see chart 1). The disadvantage is that the technology deposition efficiency is low, deposition time is long.

　　Third class: composite technology.

　　So-called composite process is the above two kinds of combination of preparation of carbon/carbon composites brake pads, such as the CVD process is the matrix of carbon fiber surface formed gradually grow. Suitable for smaller gap between the carbon fiber. Because big gap around small pore filling and block sedimentary gas source, formation of materials in the big hole, and dipping carbonization process, as a result of the impregnated resin or pitch carbonization is internal contraction form spherical matrix carbon, often out of contact with the surrounding carbon fibre, forming uniform small gaps. Big hole left by the CVD technology so easily be impregnated carbonized matrix carbon in small gaps formed between the fiber is suitable for CVD carbon offset. Can reduce the increase of the combination process time, improve production efficiency. The drawback is that process equipment complex, large investment. Adopting the technology producing carbon brake disc manufacturers have bjgreatwall company

　　Carbon carbon composite material for a series of unique mechanical, thermal and tribological system can replace the metal base composite material of a new generation of brake materials, its main characteristics are as follows:

　　Density is small, the density of the material at about 1.8 g/cm3, is 1/3 to 1/4 of metal matrix composites. Using the materials of brake components, compared to about 40% weight loss. For military aircraft, the aircraft can be improved measure of payload and lighter; For commercial aircraft, lose weight 1 kg equivalent to 3000 litres of fuel savings annually. So the cost of its use effect is remarkable.

　　Thermal stability is good, when to stop the plane take off, the surface temperature of the brake pads of more than 2000 ℃ above, carbon/carbon composites are neither melt adhesive, also won't buckling deformation, can continue to use after cooling; More than 660 ℃, the temperature of the metal matrix composites above will generate buckling deformation, lead to melt adhesive, need to repair the brake components. Therefore, made of carbon/carbon composites brake pads can not only improve the design margin of brake components, also improves the use safety of brake components. manufacturer: Beijing Greatwall Co.,Ltd..

　　The heat capacity of the heat capacity is big, the material is 2.5 times that of metal matrix composites have good heat function, improve the heat storage capacity of heat reservoir, reduce the operating temperature of the heat reservoir.

　　Stable friction coefficient, the material in a wide range of temperatures and stable friction coefficient, the plane soft braking process, improved the aircraft brake comfort.

　　Low wear rate, long service life. For at least 2 times of metal matrix composites, reduced the maintenance of the brake components.

　　Is higher than strength, especially the high temperature strength of steel more than 2 times , compared with the metal matrix composites, the material itself can be used as structural components, don't need other material skeleton support structure, simplify the structure of the brake components, improve the reliability and maintainability of the brake components.

　　Because of the material has the above characteristics, is especially suitable for used as aircraft brake materials, so since the 1990 s, carbon brake has become the standard configuration of new aircraft and a wide range of applications.

　　Research and development on the low carbon content graphite sheet is one area of graphite sealing material. Actually,to some instruments such as farm equipment , extensive chemical machinery,it’s no need to use the high carbon content flexible graphite sheet.it’s enough that If the sealing property could be better than the asbestine,and under this situation,it could reduce costs and selling price,and it also could promote the replace of flexible graphite sheet.

　　As per the process flow:

　　Expandable graphite > High temperature expansion > Pre press > Thermal treatment > molded press > Further repression,the expandable graphite could be process to the graphite sheet.

　　According to the study showing that,the appropriate reduction of the carbon content could totally satisfied to the seal requirements of general industrial seals. Mainly from the following aspects to characterize:

　　1) The infulance to the mechanical property of carbon content and impurity.

　　Demonstrated by the experiment,the intensity and purity of graphite sheet are proportional,under the situation of low carbon content,the tensile strength is inversely proportional to carbon content,apparently,the impurity has an important influence to the mechanical property.

　　2) The infulance to the air tightness of carbon content and impurity.

　　Use the gaskets made of the flexible graphite sheet to do the air tightness test,and the results showed that the leakage rate has little relationship with the carbon content,with the increase of the carbon content,the change of the sealing properity is not obvious,and all the testing samples could meet the German flexible graphite gasket gas tightness requirements,in addition,the impurity also has a little influence with the leakage rate.

　　The influence of the carbon content is not obvious,and still could maintain the good sealing property,however,the price will be fall by 50%.

　　Graphite crucible is widely used for experiment and the melting of metals, graphite crucible material with special of high purity, high strength, high density graphite material; through high precision CNC machining equipment, can be machined graphite crucible, graphite casting crucible, graphite oil groove, slide, drawing tablets, pull rod of mould graphite products.

　　Graphite crucible for smelting noble metals selected special graphite materials, can make the graphite crucible product 2 times more than ordinary materials product durability, longer service life, more can withstand more than 2000 DEG C high temperature!

　　Characteristics of graphite crucible:

　　1. Graphite crucible is of good thermal stability: special formula for the use of graphite crucible in rapid cooling.

　　2. Graphite crucible have good corrosion resistance, impact resistance, to ensure the reliability of product quality.

　　3. Graphite crucible good resistance to acid, alkali.

　　4. Good thermal conductivity of graphite crucible: it can greatly shorten smelting time, save energy.

　　5. The ash of the graphite crucible is less than 3000pp, and the metal is not contaminated in smelting process.

The flexible graphite sheet is widely used as an engineering material because of its excellent sealing effect.the main advantage and disadvantage described below:

The advantage:

　　1)high thermal conductivity

　　The high thermal conductivity of flexible graphite sheet is much higher than PTFE and asbestos,

　　During the motive seal,the excellent thermal conductivity could sweep away the heat caused by friction.and avoid the temperature too high.

　　2)self-lubrication

　　The flexible graphite sheet is made of flake graphite,as the layered structure,it has a good property of self-lubrication.during the work time, the lamellar orientation parallel to the direction of friction,and combining power between layers is very low,and the crystal is easy to move,so the friction coefficient is very low. During the operation of the equipment,it could form a film on the surface of the metal after about 20min,and after that,the friction will only happen between the crystals instead of the metal and crystal.

The disadvantage:

　　1) the low tensile strength and flexural strength

　　Compared with other sealing materials,the tensile strength and flexural strength is lower than them,and it’s really an obvious disadvantage of the flexible graphite sheet.and it’s also lack of toughness,so the flexible graphite sheet is not suitable for sealing parts as lip,and forming packing.

　　2)the heat loss of the flexible graphite sheet.

　　The flexible graphite sheet is same as the ordinary graphite products at those property of high temperature oxidation,at about 550℃,the graphite start to oxidate,if this situation lasts long time,the accumulative total of the heat loss is very obvious.

　　to sum up,although the flexible graphite sheet is widely used as sealing ,but it still has some problem to improve,and the flexible graphite composite material is a good way to solve it,such as spiral wound gasket and adding the ceramics,Al2O3,Si3N4 and Si.so the temperature will be increase to 1260℃.

　　Carbon brushes are a type of graphite parts.Carbon brushes with a resin binder were prepared according to an industrial process and the effects of the molding pressure, grains size and cure temperature on the properties of brush samples were discussed. Four kinds of high-resistivity carbon brushes with MoS2 contents of 0%,2%,4%and 6%(mass fraction)were prepared, respectively.Wear tests of brushes were conducted on an alternate current(AC)motor.Scanning electron microscopy(SEM)and energy dispersive X-ray analysis(EDS)were used to analyze the worn surface of brushes,and a thermocouple was used to measure the bulk temperature of the brush.The results show that wear rate of brush made without MoS2 in 10%relative humidity(RH)is two times larger than that in 50%RH,whereas the wear rates change little for the brushes made with MoS2.The wear of brushes has much to do with the surface film.In low humidity,the surface film can not be formed for the former brush while a sulfur layer can be formed for the latter brushes,which can reduce sparks,frictional heat and wear rate,and play a role like the water film in high humidity.

　　The results show that the bulk density, bending strength and Rockwell hardness increase, while resistivity decreases with increasing molding pressure. Cure temperature has much more influence on the properties of brushes than molding pressure and grains size. Isothermal differential scanning calorimetry(DSC) was used to estimate the degree of cure of resin binder and a novel method of using the true density to measure the degree of cure of resin binder was presented and discussed briefly. Based on optimal process parameters carbon brushes were manufactured, durability tests for brushes were carried out on an alternate current motor and scanning electron microscope(SEM) was adopted to observe the morphology of worn surface of brushes. The results show that a luster oxide film can be formed on the surface of brushes and their service life reaches 380 h.

　　Graphite crucible is usually used in smelting metals, especially precious metals . Graphite crucible is made from high quality graphite, have good thermal conductivity and high temperature resistance, high temperature environment used in the thermal expansion is not only the number is small, but also has thermal shock resistance strain performance, acid and alkali resistant with excellent chemical stability. Multiple variety and complete specifications, used in chemical industry, casting and other industrial sectors, the steel smelting and smelting non-ferrous metal and alloy also has been the most widely used.

　　Graphite crucible due to a high temperature thermal expansion coefficient, and thermal shock has some anti-strain properties, and pH of the solution for anti-corrosive, and has excellent chemical resistance to corrosion stability.

　　Graphite crucible need to guard against damp, when handling light to take light put, it is forbidden to shock. Before use must be in the hot oven drying equipment or stove, let the temperature gradually rises to 500 ℃, avoid the furnace cover wear and tear of the following should be on the front plane of crucible crucible. Graphite crucible when feeding should be according to the crucible solvent quantity, not charging too much, too tight to avoid expansion of crucible. Both inside and outside the removal of crucible wall gently slag and stick cokes to avoid damage to the crucible. Should keep a proper distance between the furnace wall crucible, crucible should be placed on the center of the furnace. In the use of excessive accelerant, additives will reduce the service life of crucible. Finally, in use process by rotating the crucible every week, can prolong the service life of crucible.

　　Thus graphite crucible in metallurgy and casting molds, and is widely used in smelting alloy tool steel and non-ferrous metals smelting and alloys, and has a good technical and economic results.