When makingcemented carbide, the size of the raw material powder is between 1 and 2 microns, and the purity is high. Raw materials according to the provisions of the proportion of added alcohol or other medium in the wet ball mill in wet grinding, making them fully mixing, crushing, drying, sieving after adding wax or gel forming agent of a class, and then drying and sieving to prepare a mixture. Then, when the mixture is granulated, pressed and heated to close to the melting point of the bonding metal (1300 to 1500 DEG C), the hardened phase and the bonding metal form a eutectic alloy. After cooling, the hardened phase is distributed in a mesh composed of bonded metal and is closely linked to each other to form a solid. The hardness of cemented carbide depends on the content of hardened phase and grain size, that is, the higher the hardening phase content, the finer the grain size, the greater the hardness. The toughness of cemented carbide is determined by the bonding metal, the higher the bonding metal content, the greater the bending strength.

In 1923, Germany to schrotter's tungsten carbide powder with 10% to 20% of the cobalt binder, the invention of the new alloy of tungsten carbide and cobalt, hardness only to diamond, this is one kind of hard alloy made of artificial world. When the cutting tool is made of this alloy, the cutting edge of the blade will soon wear off, and even the blade will crack. In 1929, Schwarz Kopf of the United States added a certain amount of tungsten carbide and titanium carbide into the original component,which improved the performance of cutting steel.This is another achievement in the history of cemented carbide.

Cemented carbide with high hardness, strength and toughness, good wear resistance, heat resistance, corrosion resistance and a series of excellent performance, especially high hardness and wear resistance of it, even at a temperature of 500 DEG C also remained unchanged, at 1000 degrees C still have high hardness. Hard alloy is widely used as a tool material, such as turning, milling, planing, drilling, boring, used for cutting cast iron, non-ferrous metals, plastics, chemical fiber, graphite, glass, stone and steel, can also be used for cutting steel, stainless steel, high manganese steel, tool steel and other hard processing materials. Now, the cutting speed of the new carbide tool is equal to that of carbon steel.

It can also be used to make drilling tools, mining tools, drilling tools, measuring tools, wear-resistant parts, metal abrasives, cylinder liners, precision bearings, nozzles, etc..

Over the past twenty years,coatedcemented carbide has also come out.In 1969 Sweden developed titanium carbide cutting tool coating, the substrate is tungsten carbide titanium carbide cobalt alloy or cobalt tungsten carbide, titanium carbide surface coating thickness of only a few microns, but with the same grade alloy tool compared to prolong the service life of 3 times, the cutting speed increases from 25% to 50%. In 1970s, there have been fourth generation coating tools that can be used to cut materials that are difficult to machine.

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