Tools in the hottest dry cutting

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Tools in dry cutting

dry cutting has higher requirements for tools, such as tool material, tool structure and tool coating

in traditional machining, the cutting fluid in wet cutting plays an important role, but there are also many disadvantages. For example, it takes a lot of money to maintain a large cutting fluid system. At the same time, it needs to regularly add preservatives, replace cutting fluid, etc., which increases a lot of costs. The cost proportion has accounted for 15% - 17% of the total production cost, while the tool cost usually accounts for only 2% - 5% of the total cost. In addition, the harmful substances in the cutting fluid do harm to the health of workers and cause environmental pollution. Therefore, its use has brought more and more problems. From these aspects, dry cutting has more advantages

tools in dry cutting should have better high temperature resistance (thermal hardness) and wear resistance. The current tool materials, such as new cemented carbide, ceramics, CBN and PCBN, have sufficient high temperature wear resistance and can be used under dry cutting conditions. Moreover, modern cutting tool materials are more suitable for dry cutting when applied to high-speed machining. For example, CBN and advanced cemented carbide material grades, especially tool materials with coating protection, cutting without cutting fluid at high speed and high temperature is actually more efficient and life-span

requirements for tools in dry cutting

tool materials for dry cutting must have excellent thermal hardness and wear resistance to effectively withstand the high temperature of the cutting process; Low friction coefficient can reduce the friction between the tool and chip and the workpiece surface and inhibit the rise of cutting temperature; Higher strength and impact resistance to withstand greater cutting force and worse cutting conditions. In order to realize dry cutting, it is particularly necessary for tool materials to have high heat resistance (thermal hardness) and wear resistance. At present, cutting tool materials such as cubic boron nitride (CBN), polycrystalline cubic boron nitride (PCBN), diamond, polycrystalline diamond (PCD), ceramics (A12O3, Si3N4), ceramic, ultrafine grain cemented carbide and cemented carbide coating have been widely used in dry cutting. In recent two years, iska has developed many tool materials that can be used for dry cutting: ib90 and ib85. The CBN content is as high as 85% and 90%. The blade has high wear resistance and toughness, and can cope with the vibration caused by intermittent cutting. It is recommended for high-speed cutting of cast iron and intermittent cutting and rough machining of hardened steel. Brands with low CBN content, ib55, ib50, CBN content of 50% and 55%, are more suitable for semi finishing and finishing. Ib10h belongs to ultra-fine grain CBN, with higher wear resistance and toughness. It can be used for high-speed continuous cutting to obtain high surface quality; Ib20h fine grain and medium grain CBN, used for continuous slight intermittent cutting; In addition, ib10hc, ib25hc and ib25ha are coated with tin, Ti (C, N, O) and Ti (C, n), which are applied to various corresponding occasions

special tool coating

coating the tool is an important way to improve the performance of the tool. Coating materials with high heat resistance and wear resistance on the surface of the strong and tough tool matrix increases a heat insulation barrier between the tool and chips in the cutting process, prevents heat transfer to the tool matrix, reduces tool wear and generated heat, reduces the friction coefficient between the tool/workpiece surface, and plays a certain lubricating role, so coated tools are most suitable for dry cutting. For example, A12O3 is the basic component of alumina based ceramics. A12O3 coating has good mechanical properties, excellent thermal hardness and chemical stability. Therefore, A12O3 coated blade has good anti crescent wear ability and low thermal conductivity. With the increase of temperature, its thermal conductivity decreases. This characteristic can prevent the cutting heat from reaching the cutting edge of the tool and prevent the sudden failure of the cutting edge caused by plastic deformation due to heating, Iska through medium temperature chemical coating (mtcvd) α- Tec, optimized A12O3 has good oxidation stability and high thermal stability α Phase, improve A12O3 multilayer coating

generally speaking, coatings are divided into two categories: one is hard coating, that is, coating tin, tic, TiCN, TiA1N, A1 on the surface. Due to the good reputation and quality of this electromechanical in the testing equipment, such coatings as 2O3, CBN, diamond, diamond-like DLC, nano materials, etc., these coatings have high hardness and good wear resistance; The other is "soft" coating, which is coated with antifriction coating such as chalcogenide compound M0S2 or WS2 or tas2, which significantly reduces the friction coefficient. This kind of coated tool is also known as "self-lubricating tool". This kind of coated tool makes up for the lubrication effect of no cutting fluid to a certain extent, resists the rise of cutting temperature, and is very suitable for dry cutting. Iska's ic908, ic907 and ic903 are hard coatings. They use ultra-fine Grain Cemented Carbide with good mechanical shock and thermal shock resistance as the matrix. Through the PVD coating with lower friction coefficient, Jinan new era test is conducted to achieve a comprehensive, harmonious and sustainable development. More technical knowledge of gold Instruments Co., Ltd. is available in our manufacturers. Welcome to consult with art coating high temperature resistant material TiAlN, which has high oxidation resistance temperature, TiAlN film will be produced during cutting, which has good oxidation resistance. The initial oxidation temperature is 700 ℃ ~ 800 ℃, higher than the oxidation temperature of tic, tin and other coatings. TiAlN has higher hardness and better thermal stability than tin at high temperature. It produces oxide film at high temperature. It can improve the friction between the tool and the workpiece/chip and reduce the generation of heat. In addition, the thermal conductivity of TiAlN coating is also lower than that of tin and other coatings, which plays a role of heat insulation, so that the tool can withstand higher temperature during dry cutting. The hardness of PVD TiAlN coating is equivalent to that of TiCN and tin, and the thermal stability temperature is higher than that of TiCN and tin, reaching 1450 ℃. With the increase of A1 content, this TiAlN coating has higher hardness, stronger high-temperature fracture resistance, high hardness and wear resistance, while the oxidation temperature remains unchanged

in the past two years, iska has used ultra-thin tin and TiAlN to alternately coat the tools. The coated tools have the characteristics of strong adhesion, high heat resistance and good wear resistance, which integrates the advantages of tin, TiAlN and tinc coatings. Then, the coating post-treatment technology sumo Tec is used to further improve the toughness and wear resistance, reduce the surface friction coefficient, lower the temperature in the cutting area, and improve the edge collapse resistance and chip formation resistance, Thus, a more reliable and durable tool life can be obtained when processing the vast majority of processed materials. The usability of the blade increases by 20% - 280% until the oil level reaches half of the sight glass

special design of tool structure

in terms of tool geometry, the design of dry cutting tools should strive to follow the design principle of "low cutting temperature". The design of tool structure must consider to minimize the heat generated in the processing process, that is, the tool structure should strive to achieve low cutting force and low friction. Normal cutting tools cannot adapt to dry cutting. Therefore, the geometric parameters of the tool should be optimized for dry cutting, that is, the tool is required to have a large rake angle and cooperate with the appropriate shape of the cutting edge, such as the -pdr and -pdr HM groove types of various milling blades of iska, and the design of zero diamond edge and double positive rake angle is adopted, which not only reduces the cutting force, but also strengthens the strength and heat capacity of the edge

in order to reduce the cutting heat, iska sets reinforcing edges on the rake face of turning blade, slot blade and milling blade, which can form a scaly cutting surface in the contact area. The contact area between the tool and the chip is greatly reduced, most of the heat is taken away by the chip, the cutting temperature is greatly reduced compared with the ordinary blade, and the shear angle is also increased, so that the tool life is significantly improved. In addition, considering the maximum lubricity of the tool surface and preventing the formation of chip buildup, iska took the lead in carrying out hard nickel transition layer and Ti containing transition layer on the tool body, which greatly improved the hardness and lubricity of the tool body surface. The design principle of "low cutting temperature" should also be considered for the profile of the chip removal groove of the tool, so as to ensure the flow of low friction chips, so as to reduce the friction between the tool and chips in processing, make chip removal convenient and fast, and reduce heat accumulation. Therefore, iska adopts the vertical blade structure in the field of milling cutter and groove cutter, so as to avoid chip removal being hindered and increase the chip removal space of the tool body

the future of dry cutting

dry cutting processing involves not only tool materials, tool coatings, but also tool geometry, tool handle structure, processing machine tools, cutting parameters, processing methods and other aspects. This requires the development of new tool materials, and pay attention to the reasonable collocation of tool materials and workpiece materials, and prevent the diffusion and bonding of tool materials and workpiece materials during dry cutting

the research on new tool materials mainly focuses on superhard tool materials, cermets, ceramics, coatings, high-speed steel and cemented carbide with excellent performance. Iska pays special attention to the research and development of coated tools. Because coated tools combine high hardness and wear resistance, high heat resistance, high toughness, high adhesion resistance, high chemical stability and low friction coefficient, the development of dry cutting technology largely depends on the development of tool coating technology

in addition to studying the hardness, toughness and thermal stability of tool materials, there are also the adaptability of different tool materials in dry cutting, and the role, characteristics and performance of different materials to be cut in dry cutting. The design of tool geometric parameters and the reasonable determination of blade shape and geometric parameters are very important to give full play to the dry cutting performance of the tool, so iska also continues to develop blade shapes with higher strength and more reliable blade clamping methods; Consider the reasonable adjustment of the distribution of the cutter body quality to make the cutter body expand evenly, and so on. For geometric parameters, we emphasize the principle of small cutting force and low cutting temperature

dry cutting is the concrete embodiment of the production concept of environmental cleaning. It not only reduces the production cost, promotes the progress of tool technology, but also brings a new green manufacturing technology, which is the ultimate goal of the manufacturing industry. (end)

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