Application of solid lubricants in coated tools and self-lubricating tools
solid lubricants can be used in places where lubricating grease cannot be used, in harsh environments and in situations where maintenance is not required due to their excellent friction performance, high bearing capacity and wear resistance, good wide temperature characteristics and timeliness. Solid lubricants are also widely used in cutting to improve the lubrication of friction
there are three main methods to lubricate cutting: ① use cutting fluid with lubrication function; ② Apply lubricating coating on the tool surface; ③ Use self-lubricating tools
in cutting fluid, solid lubricant only plays an auxiliary role in the form of additives to improve the performance of cutting fluid; In the latter two lubrication methods, solid lubricant is the heating system of oil box and friction pair. The main shaft (1) is the main factor of hollow shaft lubrication
applied to coated tools
at present, the commonly used tool coating materials mainly focus on the collaborative development, transfer, dispersion and commercial utilization of common key technologies. All kinds of hard nitride, oxide, carbide or boride ceramics have high hardness, excellent heat resistance, oxidation resistance and corrosion resistance
due to its low formation free energy and stable chemical properties, the coating material has been widely used in aerospace, aviation, military industry, naval ships and other high-tech and military fields, and its chemical affinity with workpiece materials is small, so it can effectively play an anti bonding role between tool chip and tool tool interface. Under the condition of high temperature in the cutting area, tic, tin and other coating materials can also be oxidized to form some soft TiO2 films. Al2O3 also has considerable fluidity above 800 ℃ and can play the role of extreme pressure lubrication. From the tribological point of view, these two aspects make the coating material play a good role as a solid lubricant, which not only enhances the ability of the tool to resist adhesive wear, but also is beneficial to reducing the cutting force, cutting temperature and improving the machining quality
solid lubricant is bonded to the tool surface by coating and coating to form a solid lubricant film, which can play a lubricating effect. The solid lubricant with layered structure has strong bonding ability with the friction surface, and its own layers have low shear strength. In the cutting process, the solid lubrication film on the tool surface will be transferred to the workpiece material surface to form a transfer film, so that the friction occurs between the transfer film and the lubrication film in the cutting process. Even if the friction occurs in the solid lubricating film, Jinan new era Gold Testing Instrument Co., Ltd. welcomes users to call and consult internally, which can also achieve the purpose of reducing the friction coefficient and tool wear
applied to self-lubricating tools
self-lubricating tools mean that the tool material itself has the functions of friction reduction, wear resistance and lubrication, and can realize self-lubricating cutting without additional lubricating fluid or lubricant. Because the application of self-lubricating tools can reduce friction and wear, eliminate the cooling and lubrication system, reduce equipment investment, avoid environmental pollution caused by cutting fluid, realize cleaner production and reduce production costs, self-lubricating tools are a kind of efficient and clean green tools, which have broad application prospects in modern cutting processing
at present, there are two main methods to realize tool self-lubricating in the cutting process: ① using the tribochemical reaction under high cutting temperature, a reaction film with self-lubricating effect is formed on the surface of tool material in situ; ② The solid lubricant is directly added to the tool material to realize the self lubrication of the tool. Adding solid lubricant is an important way to prepare self-lubricating materials. The commonly used solid lubricants include MoS2, hBN, H3BO3, tas2, WS2, etc. and some soft metals (Ni, W, Al, Ti, Co, etc.), and their friction coefficient with metal materials can be reduced to 0 2。
the solid lubricant is added into the tool material matrix as an additive to form a composite tool material, which can form a continuous solid lubrication layer on the tool surface by taking advantage of the characteristics of easy dragging and low friction coefficient of the solid lubricant, so that the tool material can obtain self-lubricating characteristics. This kind of self-lubricating tool material has good high-temperature friction performance, can adapt to the cutting temperature range above 1200 ℃ and a wide cutting speed range, and can withstand high loads, and can better meet the strict requirements of advanced manufacturing technologies such as high-speed cutting, dry cutting, hard cutting and difficult to machine material processing
the addition of solid lubricant will have two effects on the performance of tool materials: on the one hand, solid lubricant can form a lubricating film on the friction surface, so as to improve the contact state of the friction interface and reduce friction and wear; On the other hand, the dispersion of solid lubricants in tool materials may lead to the decline of mechanical properties of materials. Therefore, in order to ensure the sufficient content of solid lubricant to form a continuous lubrication film and achieve stable lubrication, and at the same time ensure that the physical and mechanical properties of tool materials do not decline significantly, it is necessary to make a reasonable comprehensive balance between their physical and mechanical properties and self-lubricating properties
because this kind of self-lubricating tool material always contains solid lubricant, the tool always has self-lubricating function in the whole life cycle, and the tool material has self-lubricating ability in a wide temperature range (low-speed to high-speed cutting)
The application of solid lubricant in cutting fluid greatly improves the lubrication characteristics, bearing capacity and temperature adaptability of cutting, improves the machining surface quality, and greatly improves the performance of cutting fluid under harsh machining conditionsLINK
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