Abrasive is a cutting material used in grinding, grinding and polishing.Abrasive consists of natural abrasive and artificial abrasive. All materials in nature that can be used for grinding or grinding are collectively referred to as natural abrasive.
People have been using abrasive for thousands of years, from natural ore to artificial only through a long historical period.As early as in ancient times, primitive man already used natural ore to make wooden tools and bones.The ancient egyptians used natural abrasives 4,000 years before the discovery of the park.About 2000 before the park, in the Middle East, with the development of metallurgy, the application of abrasive has been developed accordingly.The earliest record of abrasives being used to grind metal was around 1500 B.C., when weapons such as swords were widely used, and they needed to be sharpened with a magic stone to make them sharp.China is one of the first countries to use abrasive materials. In the Yellow River basin of China, stone axes, stone arrows, stone knives and animal bone and horn ornaments have been excavated for many times.In the slavery society of our country, bronze mirrors made by grinding method have appeared.Nowadays, the rare bronze carriage seen in the exhibition hall of the terracotta warriors and horses in xi 'an has been polished in many parts, showing high grinding level.
The history of abrasive application and the history of human civilization are progressing simultaneously.By the end of the 19th century, artificial corundum and silicon carbide were developed.Due to the excellent performance of artificial abrasive, it has achieved extremely rapid development and wide application in the 20th century, becoming an indispensable industry in the national economy.In the 21st century, artificial corundum and silicon carbide, in addition to being the main body of ordinary abrasive, will continue to be used in grinding with super-hard abrasive, and will also advance rapidly in non-grinding applications.
In the long history of the application of natural abrasive, human beings gradually realize that almost all the natural abrasive containing crystalline aluminum oxide, and it is the crystallization of alumina grinding effect, based on this understanding, at the beginning of the people try to contain of substances fused alumina abrasive, the grinding effect is better than that of natural abrasive, the French in 1893, 1894 German respectively to obtain the patent of the molten emery,In 1895, the French revised his original patent to use bauxite instead of emery as raw material.Higgins) melt jealous, artificial corundum development for industrialized mass production, the further development of the artificial corundum abrasive production through the scrap iron is added to raw materials, by physical method of corundum floating in the molten metal impurity, however, this method the invention of the purpose is to use pure alumina instead of alumina, alumina production from artificial corundum production, appeared many varieties of corundum products.The main difference of various products is the content of alumina, the kind of impurity and its content and the size of crystallization caused by cooling rate of melting block.
No natural silicon carbide, artificial silicon carbide was studied in the late 19th century.Special should be mentioned is American Acheson, (e. g. Acheson), he used containing alumina clay, deserve to go up the coke, the mixture to a strong current, until clay in the center of the melt cools, he in the electrode and the end of mixed materials showed that the stiffness of the bright flash, Acheson repeated the experiment many times, and the grinding performances of these hard material collected test it, the result could wear his a diamond ring.Atchison thought it was a compound of carbon and corundum, so he named it.In 1893, acheson obtained patent rights for the production of silicon carbide, making silicon carbide the first commercial artificial abrasive in the world.At that time, only black silicon carbide could be made.H produced 125 grams.It is known as a "" grinding gem" "and costs as much as $1,600 per kg.
After artificial corundum and silicon carbide were developed successfully in the 19th century, white corundum and green silicon carbide emerged successively in the 1920s, forming the basic system of artificial ordinary abrasive.From the 1920s to the 1960s is the artificial ordinary abrasive rapid development, period.Abrasive industry is closely related to the development of machinery industry and iron and steel industry. With the rapid development of steel industry, automobile industry and machinery manufacturing industry, various corundum and silicon carbide abrasive appear one after another, and the varieties become increasingly perfect, forming a complete artificial ordinary abrasive system.In contrast, artificial diamonds and CBN (or CBN) were developed only in the 1950s and began to enter the abrasive arena.
From 70 s to today, corundum and silicon carbide showed a trend emerging slowly mature in technology, and new varieties, but they are still widely used in the field of grinding, the outstanding new products are the product of sintered corundum (a brand of Norton products for SG), in the meantime, silicon carbide and fused alumina are to the grinding field, such as: refractory material, steel and cast iron smelting, electrician silicon carbide and lightning arrester, engineering ceramics, metal and nonmetal composite materials and other fields.In non - grinding use, corundum research and product development are 10 - liter active, such as high aluminum corundum.
In the 21st century, synthetic corundum and silicon carbide abrasive is still the most widely used, more than a third of all abrasive, it is widely used in the manufacture of all kinds of grinding tool, and constantly developed for the grinding USES, in 21st century, is the development direction of artificial abrasive hardness and toughness, in order to meet the high speed, heavy load and heavy grinding process requirement, to realize the economic and efficient grinding.As a result of the development of abrasive species, the trend towards special purpose, special effects, artificial diamond and CBN research will remain strong.In the field of grinding, synthetic diamonds and CBN will continue to replace corundum and silicon carbide, a process known as progression from AC to BD.A is corundum Alundum, C is silicon carbide Carborundum. B is cubic boron nitride,D is synthetic Diamond.However, in terms of toughness, general abrasive will develop high toughness corundum abrasive, which will still be used in parallel with ultra-hard abrasive.In non - grinding USES, ordinary abrasive will have a rapid development, and will become its main use.
China's artificial abrasive industry was established after the founding of the People's Republic of China.Relying on our own strength, we have established a complete system of research, production and development, and developed various artificial abrasives successively. In the 50 years since the founding of the People's Republic of China, the abrasive industry in our country has grown from scratch and from small to large.There are nearly 5,000 abrasive factories in China, nearly 500,000 employees (excluding grinding wheel factories), as well as specialized research institutes and universities.China's abrasive output increases year by year.In 1952, there were over 700 tons; in 1983, the total national output was nearly 120,000 tons; in 1990, it was nearly 500,000 tons; in 1998, it was 800,000 tons; and it is expected to reach one million tons in 2000.In addition to meeting domestic needs, domestic abrasive are also exported in large quantities for the international market and gain a good reputation.The quality of domestic abrasive has also been steadily improved.As far as abrasive varieties are concerned, China can not only produce all kinds of ordinary abrasive products, but also produce all kinds of super-hard abrasive products, which can basically meet the needs of grinding.In particular, brown corundum and silicon carbide, which are the basic products of ordinary artificial abrasive, are not only the largest producer and exporter in the world, but also of top quality.China is one of the few countries in the world with good mineral resources and high grade to develop the abrasive industry, so we have a good prospect to develop the abrasive industry.
Although we have reached the international advanced level in the overall quality level of common abrasive, there is still a large quality gap in some varieties, such as zirconium corundum abrasive.We should be more soberly aware that China's abrasive industry in environmental protection, protection, labor conditions, energy utilization rate and other aspects of the international advanced level has a considerable gap.We should step up our study and research, and at the same time strengthen international exchanges to shorten and eliminate these gaps as soon as possible.
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