With alkali castable SiC amount of cement kiln

Different binders for Sic Refractory Abstract: waste ceramic powder, Guangxi white clay, silicon carbide, silicon powder as the main raw material, calcium aluminate cement as binding agents, add water and alkali configured castable. By adjusting the amount of added silicon carbide, silicon carbide impact study alkali castable and alkali erosion mechanism castable. The results show that: with the addition of calcium silicons increased sample volume density, compressive strength and flexural strength increased first and decreased sample surface oxidized layer of dense oxide film to prevent the erosion of alkali vapors when add 6% -8% of silicon carbide, alkali grade samples reached level, alkali erosion capacity increased significantly.
Category Industrial Technology> Chemical Industry> Portland Industrial> Industrial Refractories> Refractory Products> unshaped refractories
Keywords SiC Alkali castable

Effect of different binders for refractories description

Therefore, we must be selected for the workpiece material properties, in order to abrasive material good results. Binding agent must have the following properties: high strength, high heat resistance , a suitable hardness, small consumption of grinding , grinding efficiency , the surface roughness of the machined workpiece is better , fillers must be economical, but can be dissolved acid or base , to facilitate recycling . Superhard abrasive material is used as a binder resin material , phenolic resin is widely used , in addition to the epoxy resin , a novel phenol resin, a polyurethane resin, a polyimide resin, and bakelite powder. Brown Corundums can be classified according to the type : inorganic binder and organic binder . Inorganic binders include vitrified , metal bond , magnesite binding agent. Organic binder resin binders include rubber binder. Resin binder itself has good flexibility and polished , the formation of abrasive , still has a good self-sharpening , clogging, less trimming , and high grinding efficiency, low grinding temperature, surface grinding finish, so the wide range of applications . Combine to form a diamond abrasive resin bond diamond abrasive, often applied .

Rare earth unique explanation

Rare earth and many of the unique physical and chemical properties to develop the alloy containing rare earth materials. Rare earth is not only a large number of used in military industry, silicon carbide powders, light industry, handicraft industry and transportation industry, also widely used as building materials, appliances and sporting goods such as family life.
The application of rare earth in conductive aluminum alloy, is now widely used in China, high technology is relatively mature, industrial value and economic benefit is good one area. High conductivity of rare earth alloy, usually refers to the pure aluminum, aluminum powder - magnesium - department of silicon and aluminum - magnesium alloy adding rare earth alloy, and aluminum zirconium - yttrium alloys. Mainly used in the manufacture of overhead transmission line, cable, sliding wire, wire core, general wiring, special purpose of fine lines and fine lines, aluminum wire. Its development soon, has risen from 315 V to 500 V on the high tension line, area from dozens to hundreds of was, was by the development of wire and cable and then to the conductive bus. They are at the new products, has become China's conductive aluminum alloy with high strength, large carrying capacity, long service life, wear resistance and easy processing characteristics. At present, more than 20 domestic provinces and cities, factory production of rare earth alloy wire

Rare earth can significantly reduce the inclusion quantity of two reasons

(1) the characteristics of rare earth oxides with high melting point, than the major, the proportion of about 2.5 times higher than pure aluminum powders. The greater the proportion of oxide, in the process of let stand, the more you will sink of inclusions, thus the remnants of the inclusions in aluminum liquid quantity the less;
(2) rare earth to join aluminium alloy liquid, liquid aluminum is smooth, does not like other refining agent boiling violently, secondary oxidation in the melting process, thus incorporated into the regenerative oxidation film (Al2O3) few in number. Deoxidization Sic Refractory of rare earth elements than deoxidizer Al, Mg, Ti, trace rare earth can make [O] strip to < 1 x 10-4%. Rare earth desulfurization ability is strong, can generate RES or RE2S3, products mainly depends on the activity of rare earth with sulfur or solubility. Rare earth elements in the fluid of the metal, also can react with O and S at the same time generate RE2O2S type sulfide. Rare earth elements can also with low melting point metal such As P, Sn, As elements combined, generate REP, RESn, REAs compounds. These rare earth compounds have the characteristics of high melting point, the proportion of light, when they are higher than the melting point of metal smelting temperature, can rise of slag. Their tiny particle becomes aluminum heterogeneous nucleation crystallization process, the removal of impurities in aluminum and its alloys. So, rare earth can make aluminum impurities redistribution, bulky compound glomeration, purification and grain boundary, improve the deformation, plastic processing of aluminum and its alloys.

Rare earth is explained in rounding of aluminum and its alloys

Studies show that of Al - Si metamorphic process directly affects the bad effect of rare earths. Stability metamorphic organization is the key to reduce the loss of rare earth, and to prevent the rare earth together, in the rare earth evenly spread rapidly to the liquid Alumina Oxides; In order to obtain stable metamorphic organization, should as far as possible to improve metamorphic temperature, metamorphic strengthen let stand, after strictly grilled slag after refining, and as far as possible need not halogen element flux for refining and cover. Rare-earth has certain incubation period, must maintain a certain amount of time at high temperature, rare earth can maximize metamorphism.
Purification effect
Rare earths to gas and the impact on the rate of pinhole
Aluminum and its alloy in the casting process, a large amount of gas will dissolve in liquid aluminum, mainly hydrogen (about 85% of gas in liquid aluminum), followed by oxygen and nitrogen. Hydrogen source is mainly in charge of water vapor, aluminum ingots and leftover material of oil, water, and on the surface of the aluminium ingot aluminum "rust" - Al (OH) 3. Hydrogen is the main reason for the aluminum powders casting of pinhole, and significantly reduce the strength of the aluminum. All can in rare earth added to the aluminum and its alloy degassing effect. When less than 0.3% for the amount of rare earth, rare earth in addition to the obvious effect of hydrogen, reduce the amplitude of pinhole rate is the largest also. After more than 0.3% when the content of rare earth, rare earth content increases, the hydrogen content is slowed down. If Y, single rare earth La, when rare earth content more than 0.3%, the increase of the content of rare earth makes hydrogen content started to rise again, changes in the rate of pinhole has the same rule, but the change is more obvious. The author thinks that to hydrogen effect in order to Y > La > Re (mixed rare earth); From the content, a single rare earth content is less than 0.3%. Rare earth with oxygen, nitrogen can generate a kind of refractory compounds Re2O3 and ReN2. In the process of smelting, mostly in the form of slag elimination; At the same time, when temperature is less than 200 ℃, rare earth and fluorine, chlorine violent action can generate of rare earth and rare earth chloride, fluoride to remove fluorine and chlorine in aluminum. So, the rare earth in the aluminum alloy can be used as purifying agent.

Garnet evaluation of choose and buy

Assessment and the choose and buy of garnet in color, transparency, is based on the particle size. The standard requirement of gem grade garnet sand: transparency is good, bright color, particle size greater than 5 mm. Emerald green garnet is very popular in the international gem market, pure and flawless, color bright, glittering and translucent get rid of the emerald green garnet value is very high. Emerald chrome vanadium aluminum garnet (also known as sand fry stone) value is very high, good quality can be compared with emerald. Red and orange red garnet is also very precious, orange orange garnet (also called spessartine) price increases rapidly in recent years.
Garnet is one of the high-grade gem, including green gemstone belongs to the rare species. Variety is more, pure color, transparent purple tooth of the market. Its refractive index is high, strong luster, color diversity of beauty, is a popular gem varieties. Many countries in the world dental purple as the "January birthstone, symbol of loyalty, friendship, and chastity. Westerners believe that purple tooth wu has the save people's lives or magical effect; In the Middle East, purple tooth wu were selected as royal tribute.
Assessment and the choose and buy of garnet in color, transparency, is based on the particle size. The standard requirement of gem grade garnet: transparency is good, bright color, particle size greater than 5 mm. In the international gem market, pure and flawless, bright color, glittering and translucent get rid of the garnet value is very high. Emerald chrome vanadium buy brown fused alumina garnet highest value, high quality can be compared with emerald. Red, orange red garnet is also very valuable. Purple tooth wu is now one of the more common low-standard gems. Variety is more, pure color, transparent purple tooth of the market. Its refractive index is high, strong luster, color diversity of beauty, is a popular gem varieties. Many countries in the world dental purple as the "January birthstone, symbol of loyalty, friendship, and chastity. Westerners believe that purple tooth wu has the save people's lives or magical effect; In the Middle East, purple tooth wu were selected as royal tribute. Geological museum of China, with an orange red spessartine big crystal, weighing 1397 carats, which are found in xinjiang. By the national museum of natural history of the world's best a brown yellow transparent cinnamon stone grossular (iron), is a carving exquisite Christ's head, weighs 61.5 carat, is priceless.
Garnet imitation goods is few, very easily, respectively.
1, if the garnet color ultra bright transparent, if the price is very attractive, go easy.
2, the cotton impurities, garnet outside have black spots, ice crack very easily.
3, garnet heavier than individual crystal, measure under in your hands, if is lighter than powder, be careful.
4, garnet contrast is exquisite, appearance, feel is very slippery, it feels very comfortable oil feeling ~ not powder "glass".
5, garnet, strong luster, look have metal feeling that bright light have a hazy feeling, it is particularly obvious on the nib.