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Information × Registration Number 0224U001314, 0121U100583 , R & D reports Title Creation of composites from KNB powders with multicomponent vacuum coatings and cutting tools based on them for processing iron-carbon and heat-resistant alloys popup.stage_title Head Klymenko Serhii A., д.т.н. Registration Date 21-01-2024 Organization V. Bakul Institute of superhard material of the National Academy of Sciences of Ukraine popup.description2 Superhard composites for tools with increased physical, mechanical and operational properties, intended for machining iron-carbon and heat-resistant alloys, have been created. It was established that the application of gas transport deposition of Ti on the surface of cBN grains allows to control the structure of the composites and obtain a uniform distribution of the ceramic matrix between the cBN grains, provided that individual grains of the superhard phase are encapsulated in it. New composites contain chemical compounds as the interaction with Ti (such are TiN and TiB2) in addition to cubic boron nitride cBN. The use of composites obtained from initial coated powders (3–8% Ti) in the cutting tool allows for a 20% reduction in the tool wear rate during high-speed (220 m/min) cutting of hardened steel compared to a tool equipped with a standard PcBN composite. Under predominant abrasive mechanical wear at a speed of 110 m/min. the efficiency of the tool with the new composite is relatively low. During high-speed machining under dynamic shock loads, the new composites, unlike the BL-PcBN composites, retain their workability at feeds of 0.1 and 0.38 mm/rev. (with a reinforcing chamfer) and ensure surface quality Ra 0.4–0.6. With the use of a specially developed algorithm, statistical theory of extreme values and assessment of probable level 5 microdamage in ceramic phases, a study of the influence of microstructure on the stress state, elastic moduli and brittle strength of two- and three-phase ceramics was carried out. The choice of optimal (regarding operational characteristics) structural parameters of cBN-TiN ceramics is justified. Simulation data show that the strength of ceramics made from coated powders, other things being equal, is 1.1-1.3 times higher than that of ceramics with the same phase composition, but made by the traditional technology of mechanical mixing. Product Description popup.authors Klymenko Serhiy A. Kopieikina Maryna Yu. Manovitskii Olelsandr S. Manokhin Andrii S. Melniychuk Yuriy O. Mukovoz Serhii Yu. Naydenko Аrtem G. Ryjov Uriy E. Chumak Anatolii O. popup.nrat_date 2024-01-21 Close