How to identify black silicon carbide

Black silicon carbide as chemical stability, high thermal conductivity , thermal expansion coefficient, good wear resistance , except for the abrasive used , there are many other uses , for example: a special process the silicon carbide powder coating on the turbine impeller or cylinder block the wall, can improve the wear resistance and extended service life 1 to 2 times ; made ??of high-grade refractory to , thermal shock resistance , small size, light in weight , high strength, good energy saving effect .
How do black silicon carbide identification:
1 Appearance Density : And you want to see the density of silicon carbide , silicon carbide and high chamber generally loose content is higher than the number ;
(2) Test Hardness: It 's more than the glass hard , can use when glass cutter ;
3 see color: from the color , the difference with green silicon ;
4 experiment : to find a glass container , put the pieces into a certain amount of silicon carbide , add water , shake , look at its turbidity , water darker , indicating its higher carbon , silicon carbide, but less ; the water drained , look silicon carbide in the quartz sand how many unfired raw numbers , then make a preliminary judgment, if you engage in over- testing, your judgment will not be up and down the error 3 .

Green silicon carbide powder magnetic separation is very important

Green silicon carbide is a high temperature high-tech products , its color is green, crystal structure is shaped products, microscopic shape of a hexagonal crystal , silicon carbide Mohs hardness of 9.2 , a Vickers hardness of 3000 - 3300 kg / mm 2, the Knoop hardness of 2670-2815 kg / mm , hardness of 3300 kg per cubic millimeter.
Green silicon carbide material to be crushed by magnetic separation . Green silicon carbide powder is very important that such general magnetic material after the wet- milled into a concentration of 25 % to 40 % of the slurry for wet magnetic separation to remove iron into the milling time , the production scale is small , can be permanent block wet magnetic separation . The aircraft magnetic field strength of 7000 Oe or more , stopping every 20 ~ 30min filters cleaned once removed , can make the material magnetic material content to 0.002% or more, when the large-scale production , can be wet magnetic separator as CST162 electromagnetic iron machine . Green silicon carbide powder Scope: do bonded and coated abrasives , and polishing , machining cast iron , tungsten carbide, titanium, high-speed steel , etc., can grind glass, ceramics, stone , agate and jade fine jewelry other non-metallic materials, heating elements and thermal elements , such as : Carbide , optical glass, glass and ceramics and other hard and brittle ma non-metallic materials , can also be used to manufacture high-grade refractory , electric components and electrical component products.

About emery introduce the main functions

Emery Because high temperature, corrosion resistance, high strength and other properties, it poured with steel sliding gate, smelting rare metals, special alloys, ceramics, blast furnace lining (walls and tubes); chemical containers, spark plugs, anti- Thermal oxidation resistant coating.
Because of hardness, wear resistance, high strength characteristics, in the chemical system, used to do all kinds of repercussions vessels and pipelines, chemical pump parts; make machine parts, all kinds of mold, such as wire drawing dies, extrusion die nozzle pencil etc.; make tools, dies abrasives, bulletproof material, human articular, seal mold ring.

brown fused aluminium oxide insulating material, such as lightweight corundum bricks, corundum hollow spheres and fiber products, used in various high-temperature furnaces throughout the furnace wall and roof, both high temperature insulation. Size sand corundum corundum block by artificial selection, admission on the roll, ball mill, and other settings Barmac deployment processing equipment, particle size by the F8-F325. Important for polishing, grinding, industrial grinding, etc., you can also press customer requirements at washing, pickling disposal punishment essentials processing, the difference can probably satisfied customers demand.

Britain at the end of low-carbon corundum furnace and special process and then dispose of punishment, corundum low carbon content in the waste, so that the product is not in use powder, not burst, toughness is the Carborundum Abrasives
industry, refractory material industry of choice material. Emery important for ceramic abrasive, high abrasive, organic abrasive, abrasive belt, coated abrasives, etc., credentials residual carbon content is divided into: calcined corundum C ≤ 0.05%, carbon corundum C ≤ 0.10% , ordinary corundum C ≤ 0.15%.

Explains how to better develop the corundum

Corundum is the most common major abrasive a product, the product has many advantages, abrasives carried out related to the conduct. Current national exercise restraint corundum, screening exercise small stove, but in fact is encouraging enterprises to take a group of road.
Known as dental abrasives industry reputation. Commonly used in the grinding or abrasive abrasive grinding thing as the parts to be processed to be machined, and reaches a certain skill requirements. Twelfth Five-Year Plan "beginning to carry out abrasive professional conduct has brought great opportunities and challenges. Energy conservation, hygiene production will showcase the produce in abrasive occupational category, in addition, the state machinery , shipbuilding, automobiles, airplanes and other areas of policy will also abrasive corundum abrasives production and carry out a great impact.
As a special abrasive incomparable career, there is abrasive in terms of energy saving exercise problems, current domestic overcapacity corundum appearance, followed by the implementation of national energy conservation policy, the next step will be a screening approach point behind corundum occupations capacity. Estimates of future five-year career abrasives tone will also be carried out throughout the country's economic policy tone.
Our abrasive mall after nearly a decade of conduct, constitutes a fundamental mall format once. China has become abrasive producing countries, but not power. As a special abrasive incomparable career, there is abrasive in terms of energy saving exercise problems, current domestic overcapacity corundum appearance, followed by the implementation of national energy conservation policy, on small corundum processing Square To filter on brown corundum continue to carry out, to embark on the Group of the road.

Black silicon carbide simple way to identify what

In fact, distinguish black silicon carbide method is very simple, generally can tell from the color on the out, but some are dyed , and this time we should better understanding and from the other side to compare .
Black silicon carbide simple identification method :
Color difference compared with green silicon ; hardness, it is much harder than glass , can be used when the glass cutter ; find a glass container , put the pieces into a certain amount of silicon carbide , add water , shake , look at its turbidity , AGUA black , indicating its higher carbon , silicon carbide abrasive , but less ; the water drained , watching the black silicon carbide in the quartz sand how many unfired raw numbers , and thus make a preliminary judgment, if you engage in over- testing , your judgment will not be up and down the error 3 . There you look at the density of silicon carbide , silicon carbide and high chamber generally loose content is higher than the number .
 

There are new developments in silicon carbide carbon double success

Technology is evolving , is endless , master of science and technology to master the future , the current silicon carbide in science and technology , there has been a new development , the standard of silicon carbide prospects bright.
In an atmosphere of carbon tetrachloride carbon SiC surface layer made ??new progress in preparing for the chlorine source and carbon tetrachloride by carbide derived carbon (CDC) process and chemical vapor deposition (CVD) law , successfully prepared on the surface of the silicon carbide layer carbon . The carbon layer respectively formed by chlorination of silicon carbide and carbon tetrachloride CDC subsurface formation of pyrolytic CVD surface composition. Film forming temperature of the layer has an important role . Since the CDC chlorination process is much higher than the deposition rate of CVD process , so CDC layer is thicker than the CVD layer .
The researchers believe that by introducing hydrogen as well as ways to reduce low temperature evaporation of carbon tetrachloride CDC layer thickness. The carbon layer formation mechanism of chloride and CVD silicon carbide layers are formed , but these two competing processes occur simultaneously . The carbon layer may be used as a better interface than the CDC coatings on metal matrix composite material, the mechanical seal can also be used as lubricating coating.
Extensive use of silicon carbide , silicon carbide almost all walks of life are inseparable , but the most important of the earliest silicon carbide is used in abrasive applications on . Silicon carbide abrasive industry is one of the most basic ingredients . Although there is now a new development of silicon carbide , silicon carbide , however the most important application areas or in the abrasive article .

Black silicon carbide materials include what are

Including black silicon carbide and green silicon carbide, wherein: Black silicon carbide is quartz sand , petroleum coke and quality silica as the main raw material in electric arc furnace smelting .
Its hardness between corundum and diamond , the mechanical strength is higher than corundum, brittle and sharp .
Green silicon carbide are petroleum coke and quality silica as the main raw material, add salt as an additive in electric arc furnace smelting .
Its hardness between corundum and diamond , the mechanical strength is higher than corundum .
There are commonly two different silicon carbide abrasive crystals , one is green silicon carbide, with SiC 97% above, the main tool used for grinding hard gold .
Another black silicon carbide , metallic luster, containing SiC 95% more strength than the large green silicon carbide , but the hardness is low, primarily used for grinding cast iron and non-metallic materials .

Stone processing abrasive composition and classification

Is abrasive abrasive, binders, fillers, porosity, and attachments and other components.
The basic requirements of the abrasive:
1, the hardness is higher than the hardness of the material to be processed;
2, has a certain toughness and strength, and with sharp skills.
3, should have a certain degree of mechanical strength.
4, maintaining the inherent high strength and hardness (hardness or thermal stability or red).
Abrasive Category:
Abrasive for natural and artificial sources can be divided into two categories, according to the nature of abrasives and super abrasives can be divided into two general categories.
Common natural abrasives:
A natural diamond: diamond abrasive with high efficiency, long life, low cost, good quality grinding series of advantages.
2, quartz sand: also known as silica sand, 95% of the particles of quartz sand.
3, garnet sand: to loose abrasives for cutting soft marble blocks.
4, natural corundum: mainly composed of A1203. Mohs hardness of 9, second only to diamond.
Commonly used artificial abrasives:
1, corundum: Suitable for grinding the tensile strength of the material, the price is cheaper.
2, corundum: grinding capacity slightly higher than corundum (0.12 for the diamond). Moderately fine grinding.
3, chromium corundum: purple or pink, slightly higher than corundum grinding capacity (as diamond 0.13), especially for the profile grinding. Widely used alloy gears, cutting tools, thread management tools and instruments of precision grinding parts.
4, SiC: commonly known as carborundum, its ability to wear diamond 0.25-0.28, brittle and sharp, is very versatile and an abrasive.
5, synthetic diamond: wear ability and natural diamond almost there in the stone industry will gradually replace traditional.

Silicon carbide powder production steps are as follows

Silicon carbide powder production process there are five main steps:
First, take the silicon carbide materials, through the crusher, and sieved to less than 5mm of silicon carbide particles, and then shaping machine shaping them to no more than 2mm of silicon carbide particles, and the particles of which accounted for 80 Oval % or more, performs, pickling to remove impurities, and then during drying
Second, milling, the dried particles of silicon carbide powder mill crushed into d50 = 9.5-11.5μm silicon carbide powder, crushed when the mill is set to host the current 65-75A, fan flow is set to 40-50m3/min, analysis machine speed of 400 - 600 rpm / min for milling process.
Third, grading, grading machine with vortex flow silicon carbide powder grading, grading, vortex flow fan air classifier is 25-43m3/min, classifier wheel rotational speed of 2600 - 3300 rev / min, from grading mouth ceded ds94 = 6.5-5.5μm particle size of the finished product A, cyclone separation ds94 ≤ 5.5μm mouth semi-finished products;
Fourth, the vortex type air classifier with cyclone mouth impeller semi separated gas stream classifier then re-classifying, grading, the impeller of the fan air flow classifier 25-10m3/min, classifier wheel rotation speed is 1300 - 1700 rev / min, separated from the particle size classification mouth ds94 = 4.5-3.0μm finished product B, then the separated product cyclone mouth. Fifth, testing, according to the standard detected in the production of silicon carbide powder is qualified.

Garnet sand

Garnet sand, garnet abrasive products in the mountains of the high-quality natural garnet ore as raw material, according to the modern craft sticks refined products self-sharpening . Grinding efficiency . Sand consumption is low , grinding pieces of good finish .
The abrasive shell-shaped fracture , hardness, toughness, sharp corners , constantly smashing step in the formation of new edges and the side edge , making it superior to other abrasive grinding capacity .
It has a high hardness. Than significant . Chemically stable and its unique self -sharpening advantages , making it have the other abrasives , synthetic abrasives irreplaceable advantages, as grinding, polishing glass bulb . Monocrystalline silicon is an ideal material ; right optical Industry lenses. lens grinding on the printing plate , glass, crystal , ceramic products . leather stone . nuclear contamination protective plastic layer processing and electrical degrees , can obtain good results ; also sand-blasting , manufacturing grinding wheels and high-precision sandpaper emery cloth . abrasive paste . cutting discs ; water cutting sand is an ideal material ; since than the major . chemically stable for water filtration media , water purification ; due to its wear . Aciduric alkali, use it for filling agent manufacturing wear-resistant rubber . wearing plastic , non-slip paint and other new products ; using it as cement filler, can be made efficient wear cement, is the construction of motorways. airstrip . pier. entrance of the hotel . parking sporting venues . resistant floor of advanced materials such as high-grade building ; using its micro- level products , applied to the tile surface can be made ??"permanent" wear-resistant floor tiles, floor tiles improve wear non-slip and strength properties .