Graphite mold is mostly carbon, part of the air so that the graphite prone to oxidation at high temperatures, Typically graphite oxide at about 500 ℃ start, and with the graphite mold temperature increases the oxidation rate of oxidation of geometric growth intensified.Graphite mold is mainly graphite machining, and the periphery of each of the carbon atoms linked to three other carbon atoms covalently bonded to constitute a covalent molecule.

　　Graphite mold has been used following areas:

　　1. artificial graphite die for hot pressing sintering of cemented carbide has the following characteristics: if pressed when the temperature increased to 1350-1450 degrees, the pressure can be reduced to the desired unit 67- 100 kg / sq cm (that is, cold pressure of 1/10) can;

　　2. graphite mold has been successfully applied on centrifugal casting . In order to prevent the burning of artificial graphite mold, oxidation can take certain measures .

　　3. molten metal directly continuous (or semi-continuous) bar or tube manufacturing and other advanced production methods. Artificial graphite as a non-ferrous metal continuous casting or semi-continuous casting mold is considered the most suitable material.This not only greatly improve the yield, reduce scrap loss, and product quality has greatly improved.

　　4. artificial graphite material has been used successfully on non-ferrous metals pressure casting . pressure die casting production of zinc alloy and copper alloy castings artificial graphite materials have been used in automotive parts and so on.

　　5. Since the graphite material having chemical stability, less susceptible to the infiltration of molten glass, does not change the composition of the glass, good thermal shock resistance graphite material, size and other characteristics with temperature change is small, manufacture become an indispensable mold material, can be used to manufacture the glass tube, pipe, and so on.

　　6. the use of artificial graphite material minimal thermal deformation characteristics of transistors can be manufactured sintering mold and brackets, has been widely used,. the graphite mold is also used in cast iron mold, the durability of the mold with a variety of non-ferrous metals. Diamond Mold requires high material hardness and good oxidation resistance, high precision machining, using high-quality raw materials, graphite molds greatly extended life and improved oxidation resistance. Hot sintered diamond tools graphite mold, charged with the dual role of the heating element and the mold support in the diamond tool manufacturing process, graphite mold quality will directly affect the dimensional accuracy and appearance of the shape of diamond tools and so on. Under working conditions, require both heat generating element and forming a graphite mold having conductivity, high electrical resistivity, adequate mechanical strength, but also it has good oxidation resistance and long life, in order to ensure the diamond dimensional accuracy and high performance tools.

　　What is ultrathin graphite sheet?is it any different from the ordinary graphite sheet?

　　The processing of ultrathin graphite sheet is similar to the ordinary ones:

　　The expanded graphite powder with purity of >98%, put a certain amount of expanded graphite into the hot pressing die,meanwhile,vibrate the die to make the powder dispersed evenly,then place the die onto the powder compressing machine,set the temperature and pressure,and after that,start to heat pressing.keep this situation for a period of time,then get out the graphite sheet and heat it,and make it went through a double roller mill for several times to make finished product.

　　The simple process below:

　　What’s the main application of ultrathin graphite sheet(conductive graphite sheet)?

　　With the development of the information industry and portable electronic products,heat dissipation has become the bottleneck for the continued development of electronic products,the ultrathin graphite sheet has a good performance of electrical conductivity and thermal conductivity,along the direction of crystal lamellae,the thermal conductivity can be more than 2000W/m.K,and it has an adventage of small expansion coefficient and low density,if it could be widely used,then the problem of the shortage of metal and heat dissipation of electronic components could be solved.

　　Through research by SEM,XRD and Raman on the microstructure, crystallite orientation etc. we could know the reason that ultrathin graphite sheet has a good performance of electrical conductivity and thermal conductivity,the microstucture of the ultrathin graphite sheet with high crystallization and crystallite orientation exhibited high anisotropy and the degree of the ordering of the surface carbon atom was closly to that of the flake graphite.

　　Graphite plates with different dimensions are machinined from the raw material of the graphite blocks , we can make the machining according to the requirements and use situation of the customers , and it can be dicided into three kinds with the different kind of material . isostagic graphite plates , moulded graphite plates and vibracation graphite plates . Graphite blocks have good resistance to thermal shock, oxidation and corrosion, and have suitable resistivity and homogenous structure. They have been used extensively in industries like solar, foundry, chemicals, electronics, ferrous metals, high-temp, processing, ceramics and refractory.

　　Graphite plates,It can be used to put as lining of metal tundish. The tundish function is to take the liquid steel slag and directing it to a nozzle for atomizing purpose. Our graphite plates can resist much higher temperature of over 2500 Centigrade,it can instead of cutting the plates from graphite electrodes.

　　The advantages of the graphite plates is as below:

　　1) High temperature resistance ,corrosion resistance, good thermal shock resistance ,good electric conductivity ,thermal conductivity, and also featured by strong mechanical strength at high temperature and low coefficient of thermal expansion

　　2) Highly anisotropic, particularly in respect to electrical and thermal conductivity , graphite foils and sheets are available in different thickness, graphite sheets are manufactured u n-reinforced . impregnated or reinforced

　　3) Graphite sheets made through the advanced chemical treatment and mechanical procedure without fibers ,binders, crack or other additives . it is excellent temperature resisting lubricating , electricity conductive as well as fireproof material for industrial application . and it offers excellent sealing capabilities under extreme conditions with a longer life and less maintenance.

　　Graphite sheet disperse rate is over 50. as a result it can shorten the smelting time and reduce the production cost .

　　The flexible graphite sheet is widely used as sealing material in all kinds of industries,however,it has an advantage which is the metals in contact with the graphite usually get corrosion,and with the time goes by,this situation will be worse and worse.then the sealing effect will be failure,even cause a big accident.So we need to know the why this happen and where is the sulfur from?

　　Firstly ,we need to have a know on the production process of graphite sheet:

　　The raw material to make flexible graphite is natural flake graphite,in general,it is Fixed carbon with >99%,research shows that,the sulfur in the natural graphite is 200ppm below,far less than the flexible graphite (>1000ppm),then we could know that,the sulfur is not from the natural raw material,but comes from the production run.

　　The first step of the flexible graphite processing is Oxide Intercalation(chemical methods),and the most widely used intecalater is Concentrated sulfuric acid, massive sulfur element get into the graphite interlayer,after that,we could wash the graphite intercalation compounds and dry it,most acid is washed out,but still a portion remained(about 2.8%~4.5%).when the intermediate product is sent into high temperature extrusion treatment,the interlayer substance will be decomposition gasification(SO2、SO3、H2O etc.),and the gas will get into the furnace,the sulfur of the expanded graphite now is about 1000~2000ppm.after rolling the flexible graphite will be done.

　　Based on the analysis above,we could have a know that the sulfur is mainly from the Oxide Intercalation,other processing like washing,drying,extrusion and rolling,they could reduce the sulfur content.

　　So we could say that,the sulfur in the flexible graphite sheet is from Oxide Intercalation.

　　Graphite sheet is widely used in the industry of electric power, oil, chemical, instrument, machinery and diamond etc.it’s an ideal new type sealing material and could replace rubber, fluoroplastics and asbestos in using for pipe,pump, valve.

　　With the acceleration of electronic product upgrading,and smaller and smaller and the demand for radiator pipe of high performance electronic devices, the new technology of heat dissipation of electronic products, that is, graphite material heat dissipation has been widely used.this kind of new graphite heat dissipation material take advantage of the heat dissipation efficiency, small footprint, light in weight, heat conduction along the two directions etc.

　　We know that the flexible graphite,like graphite sheet, is made of the natural flake graphite,acturally,the natural graphite need to be further processing to expansible graphite and then to used for flexible graphite.

　　Under appropriate conditions, acid, alkali metal, salt, can be inserted into the graphite layers, and combine with carbon atoms,to form new chemical phase——Graphite layers of compound,this compound could break down instantly when the temperature become fit. expand graphite along the C axis to form a new substances,and that is the expansible graphite.

　　After intercalation, deintercalate, extrusion, pressing,the crystal structure of expansible graphite is still not changed so the chemical stability and corrosion resistance of expanded graphite is good,it has a good stability almost to all of the acid, alkali, salt, organic solvents, oils, etc.it can be applied to pH 0~14.

　　The flexible graphite sheet is only one production of the expansible graphite,it could also used to make expanded graphite yarn, braided graphite tape, braided expanded graphite cloth, braided graphite tube/sleeving, die-formed graphite ring etc.

　　Flexible graphite is a soft sheet form of compressed natural graphite made from exfoliated mineral flake(crystalline) graphite. Due to its flexible texture, it is referred to as flexible graphite to distinguish it from other forms of graphite materials: flake graphite, amorphous graphite, artificial graphite (hard graphite), graphite electrodes, graphite/carbon fiber, etc. Sometimes flexible graphite is also referred to by a manufacturer's brand name like grafoil. Flexible graphite sheet is made with pure expanded graphite. standard flexible graphite sheet product has a high purity of 99.0% carbon content. Higher carbon content gives the flexible graphite foil better chemical resistance, better thermal conductivity, and better sealing ability.

　　Standard flexible graphite sheet product suitable for most industry applications. As gasket material, it is usually fabricated into Graphite Laminate, reinforced graphite sheet and widely used in fluid sealing applications: flange gasket, spiral wound gasket, heat exchanger gasket, etc. It can also be used as solid lubricant in metal stamping and forming applications, or as heat liner in industry furnaces and other heating devices.

　　Graphite gasket sheet is made with pure flexible graphite sheet reinforced with glass fiber insert. The both sides are pure graphite sheet, the reinforced material is one layer or two layers of glass fiber. The graphite layer and glass fiber are jointed together with glue bonded. Reinforced graphite gasket is cut or molded from our reinforced graphite sheets. Inner and outer eyelet with SS304 or SS316.

　　Graphite gaskets having excellent corrosion resistance, high temperature resistance, excellent compressibility and recovery, widely used for piping, valves, pumps, pressure vessels, heat exchangers, condensers, generators, compressed machine, exhaust pipes, chillers. Graphite reinforced gasket can also cut into any shape of complex gaskets such as water gauge gasket, full face flange gasket and automotive cylinder head gasket.

　　Reinforced materials: stainless steel tanged, stainless steel foil, tinplate, wire mesh, glass fiber and and Aluminium foil.

　　The graphite is made of natural flake graphite,after oxide intercalation, the thermal expansion, compression molding. Graphite sheet is one kind of flexible graphite,and it’s invented in 1963. after that,it’s widely used in The United Kingdom,German,Franch and Japan.

　　The natural flake graphite is rich in China,and it’s our advantage to do the research and development on the graphite sheet.

The production method of graphite sheet:

　　Graphite is belong to the hexagonal crystal system,and it has a laminated structure,the Interlayer bonding force is very weak,so we could insert some Molecules and atoms into the interlamination by oxidation,and intermetallic compounds is formed, meanwhile expanding the spacing of layers at this step.then heat to about 1000℃ instantly after water scrubbing the compounds,the compounds between the layers separate and by this way,graphite level was pulled,after these,the graphite particle expand dozens of time rapidly along the C direction,it looks like worm under the microscope,so it’s called vermicular graphite,and also called expanded graphite,it has a great compressibility and resilience.under the pressure of mechanical force,the expanded graphite is molded,it could be put into a mould to molded or roller compaction by roll crushing mill.then the flexible graphite sheet is finished,it could form a plate or coil.

　　The flexible graphite sheet has a good temperature tolerance, corrosion resistance, impermeability and compressibility.it widely used as Gasket and filler under the condition of high temperature and corrosive medium.the graphite sheet which has a high aeolotropism,is also used as heat insulation material and conductive material,because of the thermal conductivity and conductivity of X,Y direction much higher than the Z direction.

　　The crucible made of graphite material is called graphite crucible.It has a long history to use the graphite crucible.At first the graphite crucible consists of natural graphite (flake graphite and amorphous graphite) and clay,sand,using the pottery manufacturing process to produce.it used to melt metal(copper,iron,steel etc.)

　　The graphite has a high mechanical strength, refractoriness, Thermal conductivity,could withstand repeated smelting and Erosion of high temperature solution.with the development of modern industry, the development of metal casting in electric furnace makes the natural graphite limited.

　　Since the advent of artificial graphite by the end of nineteenth Century,the artificial graphite crucibles are widely used. High purity fine structure graphite,high strength graphite,glassy carbon material broaden the application range of graphite crucible.the graphite crucibles start to use for precious metals smelting, silver refining, uranium smelting, silicon manufacturing and chemical analysis.

　　Graphite crucible can be classified into natural graphite crucible,artificial graphite crucible,high purity graphite crucible and glassy carbon crucible according to its material classification.it also can be classified into steel melting,copper melting,gold melting and chemical analysis crucibles.

　　The service life of graphite crucible is determined by the material,quality,and the use methed.the graphite crucible is usually need high purity and high density in order to avoid the pollution to the melting metal.

　　The gold melting crucible need high purity and high density,the bulk density need to be >1.80g/cm3,and the ash need to be <50*10-6.the gold melting crucible is usually made of the high purity,high density and fine particle graphite material.

　　The graphite crucible used for uranium extraction is usually big type ones. Φ400mm*700mm and Φ500mm*800mm is widely used.

　　Graphite crucible is also widely used for chemical andlysis,it includes

　　(1) Graphite crucible for sampling before furnacing;

　　(2) Making standard sample.

　　(3) Glassy carbon crucible for chemical analysis.

　　(4) Oxygen analysis

　　　Graphite electrode is usually used as extruded graphite materials, because of low resistivity of extruded graphite, conductive performance is good, the price is competitive

　　Mold geometry increasing complexity and diversification of product applications has led to the discharge of sparks getting high accuracy requirements. Graphite electrodes are the advantages of easier machining, electrical discharge machining removal rate is high, small graphite loss, therefore, part of the group of sparks machine customers gave up and switched to the copper electrode graphite electrodes. In addition, some special shape of the electrodes can not be made of copper, but are more easily molded graphite and copper electrodes heavy, not suitable for processing large electrode, these factors have caused some group of sparks machine client application graphite electrodes.

Graphite electrode with good property

　　The chemical stability: graphite at room temperature have a good chemical stability to acid, alkali and corrosion resistance to organic solvents.

　　Thermal shock resistance: graphite used at room temperature can withstand dramatic changes in temperature without damage to live, when sudden changes in temperature, little change in the volume of graphite, will not crack.

　　Welcome enquiries to our company, we will give you the best quality products and the most competitive price

　　Graphite Tubes are mainly used in the industries , and according to the production procedure difference , it can be divied into two major kinds , one is machined by the pure graphite material , such as the isostatic graphite material , moulded graphite material , extruded graphite material and vibracation graphite material , machining from the raw material in the machine . the other kind is pressed directly by moulds.

　　Graphite Tubes and are widely used in the Tooling (EDM), Mould Making (EDM), and General Manufacturing industries. Graphite Tubes are typically used in roughing EDM applications. They can also be used as flux tubes in the high temperature sintering industry.

　　We are engaged in manufacturing a wide range of high quality graphite tubes which can be used for making equipments as well as can be used for piping work. Graphite tubes can be used for handling corrosive vapors and flu.

　Graphite tubes features:

• 　Impervious, Hydro-tested upto 5kg/cm2 pressure.
• 　Excellent corrosion resistance.
• 　Excellent heat transfer.
• 　Repairable as compare to glass.
• 　Can be joined with other graphite tubes with graphite based cement for continuous piping work.

　　In order to reduce graphite oxidation in air, you may make SiC coating on graphite surface using the SiC paste . In order get longer tube service life, Please use quartz or alumia crucible to carry sample, instead loading sample directly inside tube,

　　Please feel free to contact us for the inquiry or demand of the graphite tubes.