Views: 33 Author: Site Editor Publish Time: 2017-07-01 Origin: SEPPE
Abrasive is a kind of sharp, hard materials, used for the surface grinding of soft materials. Abrasive are divided into natural abrasive and artificial abrasive. According to the classification of hardness, abrasive can be divided into super abrasive and ordinary abrasive. The range of abrasive is very wide. From household detergent, gem diamond abrasive to the most hard materials, abrasive is essential for every kind of precision products. Many natural abrasive has been replaced by artificial abrasive.
Ceramic sand has the very good strength and toughness. It has a particularly high hardness and smooth surface, can be used repeatedly. The high utilization rate of Ceramic sand is 15 to 20 times that glass beads. The particle size range is wide, can match with various types of sandblasting machine.
Steel shot is a kind of commonly metal workpiece processing material. Dealing with the surface of metal workpiece with steel shot can have the effect of adding metal workpiece surface pressure and improving the anti-fatigue ability.
Brown Fused Alumina
Brown Fused Alumina, main component is Al2O3, with medium hardness, great toughness and low price. It is suitable for processing the high tensile strength metal. Microcrystalline alumina and black fused alumina abrasives are derived varieties. Brown fused alumina called “teeth of industry” and mainly be used in refractory materials, grinding wheel, sand blasting.
White Fused Alumina
White Fused Alumina is a kind of artificial abrasive. Al2O3 content over 99%, and containing a small amount of ferric oxide, silicon oxide, the color is white. Its hardness is slightly higher than that of brown fused alumina, but the toughness is poorer. When grinding, it is easily to cut into the workpiece. White Fused Alumina has good self-sharpening, lower calorific value, good grinding ability and high efficiency. Pink corundum is its derived varieties.
Garnet is a kind of good abrasive. It is commonly used as a substitute for Sandblasting (Sandblasting) in the silica sand.After mixed with high pressure water, garnet is used for cutting steel and other materials in Water jet cutting.Garnet is also used for water purification.
One of the important performance of abrasive is hardness, it must be harder than materials for processing, people commonly use mosh hardness meter to determine various abrasive hardness. Another important performance of abrasive is strength toughness or volume. To control this performance, people can change the amount of mixing materials, such as purity, particle size and crystal structure, then make the abrasive suitable for various applications.
Abrasive products manufacturing, in addition to the powder talc and iron oxide, all the raw material should be crushed and screened, screening particle size should be 4 to 900, namely about 6 mm (millimeter) to 6 microns or more finer. Grinding wheel is a kind of main abrasive products. Abrasive cloth and sand paper are another two kinds of large output abrasive products. Other powder or granular abrasives, after screening, should be processed, such as abrasives for grinding or polishing, usually be added mineral oil or wax and other accessories, to adapt to the needs of different working conditions.
Abrasive grain refers to the abrasive particle size. According to its particle size, the size of the abrasive can be divided into grinding grain, abrasive powder, micro powder and ultra-fine powder. Among them, abrasive particle size number of grinding grain and abrasive powder is denoted by the number of mesh on every inch of the screen, the symbol is #. Such as 240 #, it is to point to every inch screen length with 240 holes. And abrasive particle size number of micro powder and of ultra-fine powder is represented by the actual size particles, the logo is "W". Sometimes it can be converted into the mesh. W20, for example, is the actual size of said abrasive particles between 20 microns ~ 14 microns, and the mesh number is # 500.
Abrasive hardness refers to the ability of abrasive surface to fight outside effect. Hardness of abrasive (such as oil stone) is adhesive bonding degree of solid abrasive when affected by external force, it is one of the basic features of abrasive. Grinding processing is the use of hardness difference between abrasive and grind workpiece.
The strength of the abrasive refers to the degree of solid. It is the ability of withstanding the applied pressure without being broken when grinding grain of the blade is quite sharp. With low strength, abrasive has low cutting ability and short service life. This requires grinding grain should have the high hardness and sufficient strength, so that can do grinding processing better.