What is called cemented carbide?
In addition to carbon atoms, a nitrogen atom and void boron atoms can enter the metal lattice, formed interstitial solid solution. With the properties of mesenchymal type carbide. They are similar to electrical and thermal conductivity, high melting point, high hardness, brittleness and is also large.The matrix of cemented carbide consists of two parts: one is a hardening phase, and the other is bonded metalIs the hardening phase transition metal carbides in the periodic table of elements, such as tungsten carbide, titanium carbide, tantalum carbide, their hardness is very high, the melting point of 2000 DEG C, and some even more than 4000 degrees. In addition, nitrides, borides, silicides of transition metals have similar characteristics, can also act as a hardening in hard alloy the phase hardening phase due to the existence of alloy with high hardness and wear resistance.Bonding metals are generally iron based metals, and cobalt and nickel are commonly usedManufacture of hard alloy, the size of raw powder in 1 ~ 2 microns, and high purity. 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 then, after drying and sieving to prepare a mixture. Then, the mixture granulation, pressure type, heated to the melting point of the metal bond (1300 to 1500 DEG C) when hardening phase and bonding metal to form eutectic alloy. After cooling, the hardening phase distribution in grid bonded metal composition in each other closely together, form a firm whole. The hardness of the hard alloy depends on the hardening phase content and grain size, the hardening phase content is higher, more fine grain, hardness is greater. The toughness of cemented carbide by bonding metal bonded gold decision. The higher the content, the greater the flexural strength
Hard alloy 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 are widely used as tool materials. 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. Hundreds of times now cutting speed of new carbide tool is carbon steel.Carbide can also be used to make rock drilling tools, mining tools, drilling tools, measuring tools, wear-resistant parts, metal abrasives, cylinder liner, precision bearings, nozzles and so onIn the past twenty years, coated carbide also come out in Sweden.1969 in the successful development of titanium carbide coated tools, the tool is a matrix of 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, cutting to increase the speed of 25% ~ 50%.20 in 70s has been fourth generation coating tools, can be used for cutting hard processing materials.
