Nowadays, cutting fluid normally no longer necessary main reason was to have coat. They arrive from cutting area through restraining bit (cutting tool) heat is conducted come the concussion of slow down temperature. The action of coating heats up protective screen just like, because it has so lower than cutting tool matrix and workpiece material that much heat conducts coefficient. Accordingly, the quantity of heat that these cutting tool absorb is less, can bear higher cutting temperature. No matter be turning or milling, coating cutting tool allows to use more efficient cutting parameter, and won't lower cutting tool life. Coating ply is in 2 arrive between 18 micron, it is having main effect in side of cutting tool performance. Thinner coating is than thick coating when concussion cutting, the function that undergoes temperature change is close friends, because thinner coating stress is lesser,this is, produce crackle not easily. When cool quickly and heating, thick coating heats lickety-split just like glass cooling and same, allow easy go to sticks and staves. Undertake with scumble layer razor blade life is as high as 40% doing type cutting to be able to lengthen cutting tool, this is physical coating commonly used will besmear the reason of circular cutting tool and mill razor blade. PVD coating often besmears so that want than chemical coating thin, be united in wedlock firmlier with outline. Additional, PVD coating can be in so low that the deposit below much temperature is on hard alloy, accordingly, the point that they use morely at be not Chang Feng benefit and big before horny milling cutter, lathe tool. Although coating material nitrogen changes titanium, have in all coating cutting tool 80% . Below the case that fights type cutting in high speed however, best PVD coating is azotic aluminous titanium (TiAlN) , its function is in high temperature is successive when cutting, excel nitrogen changes titanium fourfold, use at high speed turning for example. The cutting tool below the thermal stress condition with TiAlN more expensive to lying coating, also surpass other coating. Milling of elephantine dry type and the deep Kong Zuan of those small diameter aperture cut the position that cutting fluid reachs hard. TiAlN is harder than TiN below cutting temperature, and have thermal stability, PVD coating used it fight chemical abrasiveness can, its hardness is as high as Vickers 3500 degrees, its working temperature is as high as 1470 ° F. Material scientist is conjectural: These property can be attributed to the alumina film that is not crystallization, it is to become after a few aluminium in surface of the coating when high temperature oxidize, cutting bits / form on cutting tool interface. This research is chosen designedly ultrathin and multilayer PVD coating, the coating that this kind of deposit process produces is comprised by about a hundred, each only rice of a few accept is thick. And the coat that the deposit of general PVD coating has ply of class of a few micron only. Although PVD coating has a lot of advantages, but metal of most to treatment black, CVD coating is remained more welcome. In CVD treatment process, deposit temperature conduces to higher increase combinative strength, and allow is higher cobaltic content in matrix, the tenacity of such edge is good, rise fight plasticity metabolic ability. Because CVD coating is thicker than PVD coating, passivation undertakes in their point point with respect to the requirement, flake in order to prevent coating, also can conduce to those who raise cutting tool fighting abrasiveness at the same time can. Allow to use feed to be able to be amounted to 0.
035 inches / turn. CVD is deposit on cutting tool the process of an useful alumina, this is people is hep most heat-resisting and the coating that fight oxidation. Alumina is undesirable conductor, the quantity of heat that it is out of shape cutting tool and cutting and generates is separated, make quantity of heat flow in cutting bits. This is a kind of wonderful CVD coating material, basically use at be in to do the hard alloy lathe tool that when cutting, uses. It still can protect matrix when high speed cutting, it is best fight abrasive to wear away with coating of crescent moon depression tatty. Coating razor blade has longer cutting tool life, it cuts milling of specific humidity type in Gan Shixi stabler. Taller cutting speed can make cutting temperature lifts further. For example, in 14000 turn / cent and 1575 inches / dry type cutting is machined below the cutting speed of cent cast-iron, can heat the cutting area before cutting tool to ℃ of 600 ° ~700. Rate of its metal excision is similar to milling aluminium, be in at this moment cast-iron on the temperature of generation with respect to cutting tool of prep above convention. CNC Milling