2023-11-21

Material characteristics of graphite powder

Graphite powder is a substance that is very sensitive to chemical reactions. In different environments, its resistivity will change, which means its resistance value will change. However, there is one thing that does not change. Graphite powder is one of the good non-metallic conductive substances. As long as the graphite powder is kept uninterrupted in an insulated object, it will also be electrified like a thin wire. However, there is no accurate number for the resistance value, Because the thickness of graphite powder varies, the resistance value of graphite powder will also vary when used in different materials and environments. Due to its special structure, graphite has the following special properties:1) High temperature resistant type: The melting point of graphite is 3850 ± 50 ℃, and the boiling point is 4250 ℃. Even after being ignited by an ultra-high temperature arc, the weight loss and thermal expansion coefficient are very small. The strength of graphite increases with te

2023-03-03

Graphite mold mold polishing

The mold polishing of graphite mold is accompanied by the common use of plastic products, such as daily chemical tools and drink packaging materials. The appearance must usually specify the surface of the injection molding mold concave mold to be polished. The production of optical lenses, laser laser records and other molds are extremely high in surface roughness, so the provisions of polishing and polishing are also very high. Following and polishing not only enhances the beautiful and generosity of product workpieces, but also improves the corrosion resistance and abrasion resistance of the surface of the raw material, but also enables the mold to have other advantages, so that plastic products are easy to produce and reduce the time of production and manufacturing injection processing cycle. Therefore, polishing and polishing is an important process in the process of injection molding.The mold polishing has two meters; one is to increase the smoothness of the mold, so that the sur

2023-08-21

High power and ultra high power electrodes

The characteristic of high-power and ultra-high-power electrodes is low resistivity, allowing for a current load of 25% -40% higher than that of ordinary electrodes; The allowable current density is greater than twice; Low coefficient of thermal expansion; High flexural strength; Low oxidation loss. The production of high-power and ultra-high-power electrodes uses needle coke as the raw material, and multiple impregnations are used in the production process to increase the graphitization temperature, and corresponding improvements are made to the bonding and impregnating agents.The requirements for ultra-high power graphite electrodes are relatively strict. The volume density of the electrode reaches 1.72g/cm3; The resistivity drops to 5-7 Ω. mX10-6. Due to the fact that the current density allowed by ultra-high power is more than twice that of ordinary electrodes, the thermal stress and impact it bears increase. Therefore, the electrode requires a low coefficient of thermal expansion

2023-03-21

What is the purpose of expanding graphite

Adsorption agent of industrial oil.

Graphite physicss

The chemical properties of single -mass carbon at room temperature are relatively stable, insoluble in water, dilute acid, dilute alkali and organic solvents; burning with oxygen at different high temperatures to generate carbon dioxide or carbon dioxide; Below, single -quality carbon is more likely to be oxidized by acid; at high temperature, carbon can also react with many metals to generate metal carbides. Carbon is restored and can smell metal at high temperature.Graphite is soft, black and gray; it is greasy and can contaminate paper. The hardness is 1-2, and the hardness can be increased to 3 to 5 along the vertical direction. The proportion is 1.9 ～ 2.3. The surface area is concentrated at 1-20m2/g. Under the isolation of oxygen conditions, its melting point is above 3000 ° C. It is one of the most temperature-resistant minerals. It can conduct electricity and heat conduction.There is no pure graphite in nature, which often contains impurities such as SIO2, Al2O3, Feo, CAO, P2O

2023-05-10

How to choose the scale of scales graphite size

Scales graphite has good conductivity and thermal conductivity. It is widely used in sealing, lubrication, metallurgy, chemical industry and other industries. Different industries have different requirements for the specific parameters of scales graphite. Choosing the correct graphite graphite is closely related to its effect. Today, I will explain the correct method of choosing the graphite size of the scale:1. The effect of scale graphite particle size on expansionThe degree of particle size on the expansion of scales also has a certain effect. After experiments, the expansion rate of scales graphite is directly proportional to the particle size of graphite. The expansion graphite has a rich pore structure. The smaller the grain size of the graphite. The smaller, the lower the expansion coefficient, and vice versa. Therefore, in the fields of sealing and fire -resistant coatings, large -scale scales should be selected as materials.2. The effect of scale graphite particle size on smo

2023-09-21

How to distinguish the advantages and disadvantages of graphite

The first aspect is the flexural strength of the material. The flexural strength of a material is a direct reflection of its strength, indicating the tightness of its internal structure. Materials with high strength have relatively good resistance to loss during discharge. For electrodes with high precision requirements, it is recommended to choose materials with better strength.The second aspect is the Shaw hardness of materials. In the subconscious understanding of graphite, it is generally considered a relatively soft material. But actual test data and application situations show that the hardness of graphite is higher than that of metal materials. In the special graphite industry, the commonly used hardness inspection standard is the Shore hardness measurement methodThe third aspect is the average particle diameter of the material. The smaller the average particle size of the material, the more uniform the discharge of the material, the more stable the discharge condition, and the

2023-09-08

The densification process of carbon graphite materials

With the continuous expansion of the application field of graphite materials, more and higher requirements have been put forward for it. Therefore, it is necessary to introduce new supplementary process methods in industrial production to facilitate the acquisition of products with special properties that cannot be obtained using ordinary methods. This process method is the compaction of carbon graphite materials.Carbon graphite material is a porous material, with a densification process that involves filling the pores or coating surface of carbon graphite material with different forms of carbon, metal, alloy, or other non-metallic substances. The purpose of densification process is mainly to improve the density, strength, conductivity, thermal conductivity, corrosion resistance, and wear resistance of the product, and sometimes to ensure that the product is impermeable to gases and liquids. However, there is a limit to compaction, and it is not possible to require all the pores in th

2023-02-22

What are the characteristics of graphite board?

The use of graphite board is so common, so what characteristics does it have?1. Easy process performance of graphite board: graphite board can be cut into different sizes, appearances, and thin thickness. It can give the membrane cutting plane board, which can be thinned from 0.05 to 1.5m.2. The heat resistance of graphite board: The temperature of the graphite board can reach 400 ° C, which can be less than -40 ° C.3. High -transmission thermality of graphite board: The thermal conduction rate in the plane map of the graphite board can achieve 1500W/mk, the heat transfer coefficient is 40%lower than the aluminum, 20%lower than the copper.4. The coordination ability of graphite board: The graphite board is very easy to make a multi -layer board with metal materials, cable shestages or double -sided tape to enhance the coordination ability of the design scheme and can have adhesives behind it.5. The lightness of graphite board: graphite board is 30%lighter than the same specifications,

2023-04-19

How does pungeable graphite produce?

Because graphite is a non -polar material, it is difficult to use the small polar organic or inorganic acid intercourse alone, so oxidant is usually used. The chemical oxidation method is generally soaked in the solution of the natural scales in the solution of the oxidant and plug -in agent. Under the action of a strong oxidant, graphite is oxidized, making the macromolecular molecule of the graphite layer into a plane macromolecular with a positive charge. Due to the extrusion effect of the iconic charging between the plane macromolecules with a positive charge, the spacing between the graphite layer increases, and the plug -in agent is inserted between the graphite layer and becomes a graphite. When heating at high temperature, puffed graphite will quickly shrink, and the contraction multiple is as high as tens to hundreds or even thousands of times. The apparent volume of shrinking graphite reaches 250-300 ml/gram or more. The contracted graphite is worm -like, with a size of 0.1