Refractory manufacturers analyze the classification and use of corundum bricks

Corundum brick refractory refers to refractory material whose main crystal phase is α-Al2O3 (corundum). Due to its excellent properties such as high temperature resistance, high hardness, high strength, oxidation resistance, corrosion resistance, electrical insulation, good air tightness, etc., with the development of modern science and technology, the application range is getting larger and larger.

 

Because industrial alumina is a loose crystalline powder with a porous and loose structure, it is not conducive to contacting Al2O3 crystals with each other, which is not conducive to sintering. Industrial alumina cannot yet produce refractory materials directly. It needs to be re-crystallized by calcination or electrofusion to transform γ-Al2O3 into α-Al2O3 (corundum) to sinter and densify it. Therefore, according to the production method, corundum is divided into light-fired (1350-1550 ℃) corundum (also known as light-fired α-Al2O3), sintered (1750-1950 ℃) corundum, and fused corundum. According to the crystal morphology, corundum is divided into plate-shaped or flake corundum, columnar corundum, granular corundum, single crystal corundum, microcrystalline corundum, β-corundum, αβ-corundum. According to the appearance color, it is divided into white corundum, brown corundum, red corundum, blue corundum, green corundum, black corundum, white blue corundum, purple corundum, transparent corundum, and yellow corundum. It is divided into chromium corundum, zirconium corundum, titanium corundum, vanadium corundum, nickel corundum, praseodymium neodymium corundum, tin corundum, miscellaneous corundum, etc. according to a small amount of other substances. According to the production method, it is divided into sintered corundum and fused corundum.

Because corundum materials are rich in raw materials and easy to supply, in terms of manufacturing process, both corundum refractory materials can be produced using traditional refractory production processes, or special refractory materials, that is, high-temperature ceramics, can be produced by methods derived from traditional ceramics. After the development and production of sunrise refractories, the technology is becoming more mature and the variety is increasing, becoming the most widely used refractories. The purpose of sunrise refractory corundum brick is as follows:

 

(1) Because of its high temperature resistance, corrosion resistance, high strength and other properties, it is used as a steel casting sliding nozzle, smelting rare precious metals, special alloys, high-purity metals, glass drawing, crucibles and utensils for making laser glass; , Such as refractory materials, ceramics, iron blast furnace lining (walls and tubes); physical and chemical utensils, spark plugs, heat-resistant and anti-oxidation coatings. Low-silicon sintered corundum bricks with SiO2 less than 0.5% are special linings for carbon black, boron chemical industry, chemical fertilizer, synthetic ammonia reaction furnace and gasification furnace.

 

(2) Due to the characteristics of high hardness, good wear resistance and high strength, it is used as components of various reaction vessels and pipelines, chemical pumps in chemical systems; as mechanical parts and various molds, such as wire drawing dies, Squeeze the pencil core die mouth, etc .; make tools, abrasives, bulletproof materials, human joints, sealed grinding rings, etc.

 

(3) Due to the high temperature insulation, the tube and protective tube used as thermocouples, insulating porcelain used in atomic reactors, and various other high temperature insulating parts, such as platinum-rhodium thermocouples, do not reach 1720 ℃ Breathable.

 

(4) Al2O3 is an ionic crystal with a very stable structure. Used at high frequency, high pressure and high temperature, its insulation is still excellent, coupled with low loss and low dielectric constant, it is widely used in solid integrated circuit substrate tube base, housing, porcelain frame in the electronics industry , Microwave window, missile radar antenna protective cover, etc.

 

(5) Corundum products have good air tightness and are tightly airtight even at high temperatures, so they are widely used in electric vacuum, such as corundum for making various large electronic tube shells and double in-line package shells in solid microcircuits .

 

(6) Corundum thermal insulation materials, such as corundum light bricks, corundum hollow balls and fiber products, are widely used in furnace walls and roofs of various high-temperature furnaces, which are both high temperature resistant and thermally insulating.

 

(7) Transparent corundum products can be used to make lamps and microwave fairings. In addition, Na-β-Al2O3 type products are dielectric materials for the manufacture of sodium-sulfur batteries.

 

Zhengzhou sunrise Refractories Co., Ltd. specializes in the production and processing of various standard shaped zirconium bricks, chrome corundum bricks, chromium oxide bricks, sintered chromium corundum bricks, aluminum chromium bricks, silicon carbide bricks, high aluminum silicon carbide bricks, mullite silicon carbide bricks Brick, corundum silicon carbide brick, corundum mullite brick, mullite brick, mullite light brick, alumina hollow ball brick, high temperature kiln furniture, sillimanite brick, andalusite brick and other high-grade refractory materials. I look forward to receiving your inquiry and serving you sincerely.