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Presents the results of the study of the main factors for improvement of the efficiency of high-performance cutting of structural steels. It has been revealed that such improvement should be implemented on the basis of simultaneous enhancement of cooling and lubrication medium (CLM). It is shown that the standard methods of supplying CLM to cutting area or use of air ionized by corona discharge as process medium are not able to effectively cool cutting area during blade cutting because of balance of endothermic and exothermic reactions. The study has considered the possibility of enhancement of CLM on the basis of Ranque-Hilsch Effect, the use of which during cooling of air flow in vortex tube allows overcoming the dew point, resulting thereby in intense air humidification and substantial enhancement of lubricating effect of process medium. It has been found out that cumulative effect of efficient cooling and enhancement of lubricity of ionized air process medium contributes to improvement of the basic characteristics of cutting process, improves tool life and significantly increases the efficiency of high-performance cutting. [ABSTRACT FROM AUTHOR]

The study considered issues for improving the efficiency of machining materials used in heavy power engineering on the basis of the development of carbide tools with nanostructured multilayer coatings (NMCC) of high wear resistance. The following compositions of the NMCC were developed for investigation: Ti-TiN-(TiCrAl)N; Zr-ZrN-(ZrNbCrAl)N; Cr-CrAlN-(NbZrCrAl)N; Zr-ZrN-(ZrCrAl)N. Wide-ranging studies of various properties and characteristics of elaborated NMCC, as well as contact parameters of cutting and wear mechanisms for the carbide tools with various compositions of NMCC are used in high-efficiency longitudinal turning material of heavy power mechanical engineering. Received results of research in this study allow establishing a rational coating composition for deposition on carbide tools providing increase of machining efficiency of the materials used in heavy power engineering. [ABSTRACT FROM AUTHOR]

This work presents the results of theoretical and experimental investigation into machining of various materials without the use of conventional environmental unfriendly cutting fluids while maintaining keys technological performance parameters of machining. In this work, the machining zone was fed with small doses of cutting fluid enclosed in microcapsules. The microcapsules were about 0.8 to 30 μm in size and were made of shell impermeable to the cutting fluid. This study employed microcapsules of increased efficacy, which was achieved by introducing in the capsules, magneto-sensitive compound (Fe 3 O 4 ) with particles size of ≈ 10 nm. Investigation into the effectiveness of machining processes was undertaken using micro-capsules and nano-scale composite coating along with carbide and HSS tools with and without nano-scale composite coatings. The cutting performance of the nano-scale composite coating was investigated with associated environmental impact. It was shown that the direction of motion of the nano-scale composite coating in the liquid carrier in the immediate cutting zone was along the lines of magnetic field, with maximum concentration at the tool tip. It was revealed that, taking into account the dominating magnetic field force (50-120 times) with respect to gravity in nano-scale composite coating, the penetration ability nano-scale composite coating into of contact areas of cutting tools increased sharply compared with the specified index of standard cutting fluid. A comparison of the effectiveness of different cutting processes was carried out in dry cutting, in wet cutting using standard fluid and with the application of nano-scale composite coating with a concentration in the aqueous medium from 1.0 to 4.0%. Turning, drilling and milling operations were undertaken using coated and uncoated tools made of HSS and tungsten carbide. The evaluation of this new technology of nano-scale composite coating as a cutting fluid medium showed that the efficiency of machining using nano-scale composite coating was as good as the cutting process with the standard fluids. In addition, it was observed that using nano-structured multilayer coatings led to higher efficiency exceeding the effectiveness of machining with standard commercial cutting fluids. [ABSTRACT FROM AUTHOR]

This article studies the specific features of cathode vacuum arc deposition of coatings used in the production of cutting tools. The detailed analysis of the major drawbacks of arc-Physical Vapour Deposition (PVD) methods has contributed to the development of the processes of filtered cathodic vacuum arc deposition to form nanoscale multilayered composite coatings of increased efficiency. This is achieved through the formation of nanostructure, increase in strength of adhesion of coating to substrate up to 20%, and reduction of such dangerous coating surface defects as macro- and microdroplets up to 80%. This article presents the results of the studies of various properties of developed nanoscale multilayered composite coating. The certification tests of carbide tool equipped with cutting inserts with developed nanoscale multilayered composite coating compositions in longitudinal turning (continuous cutting) and end symmetric milling, and intermittent cutting of steel C45 and hard-to-cut nickel alloy of NiCr20TiAl showed advantages of tool with nanoscale multilayered composite coating as compared to the tool without coating. The lifetime of the carbide inserts with developed NMCC based on the system of Ti–TiN–(NbZrTiCr)N (filtered cathodic vacuum arc deposition) was increased up to 5–6 times in comparison with the control tools without coatings and up to 1.5–2.0 times in comparison with nanoscale multilayered composite coating based on the system of Ti–TiN–(NbZrTiCr)N (standard arc-PVD technology). [ABSTRACT FROM AUTHOR]