Obrabotka Metallov 2019 Vol. 21 No. 1

OBRABOTKAMETALLOV Vol. 21 No. 1 2019 32 TECHNOLOGY Hybrid Technology of Electrochemical Processing of Complex Profiles Mikhail Borisov a , Dmitry Lobanov b, * , Alexander Yanyushkin c I. N. Ulianov Chuvash State University, 15 Moskovsky Prospekt, Cheboksary, 428015, Russian Federation a http://orcid.org/0000-0001-9084-1820, borisovmgou@mail.ru , b http://orcid.org/0000-0002-4273-5107, lobanovdv@list.ru , с http://orcid.org/0000-0003-1969-7840, yanyushkinas@mail.ru Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science. 2019 vol. 21 no. 1 pp. 25–34 ISSN: 1994-6309 (print) / 2541-819X (online) DOI: 10.17212/1994-6309-2019-21.1-25-34 Obrabotka metallov - Metal Working and Material Science Journal homepage: http://journals.nstu.ru/obrabotka_metallov ARTICLE INFO Article history : Received: 14 December 2018 Revised: 21 January 2019 Accepted: 11 February 2019 Available online: 15 March 2019 Keywords : Electrochemical grinding Electrochemical polishing Hybrid technology Diamond head Ceramic coating ABSTRACT Introduction. The development of modern processing technologies for structural materials has significantly increased the requirements not only for equipment, accessories and tools for implementing processes, but also for the quality of machined surfaces. Particularly acute this problem can be traced when creating products of an individual complex profile, often produced by individual technologies, which leads to the need to reduce costs while maintaining production efficiency. The most widely used parts of this type were found in shipbuilding, aircraft manufacturing, mechanical engineering, and medicine. For the mechanical (manual) processing of the metal frame during dental prosthetics, rotary instruments are used, including dental drills. They are equipped with collet chucks, in which carbide mills, grinding corundum heads on a ceramic bond and diamond heads on a metal bond are installed. Diamond heads on a metal bond are used only for processing products that are not then covered with ceramics. It is not recommended to use them for machining metal frames under ceramic coating, as diamond heads on a metal bond leave scratches in which gases can accumulate and stagnate during the ceramic firing process, leading to defects in the ceramic coating. In addition, during the treatment, the tool becomes “salted”. It became necessary to interrupt the process and clean the diamond heads in a sandblaster. Objective. The paper solves the problem associated with ensuring the possibility of using high-performance diamond heads on a metal bond for mechanical (manual) finishing of metal frames for further coating with ceramics by applying and combining known methods of electrochemical grinding and electrochemical polishing of products (hybrid finishing technologies). Results and discussion . Studies are carried out by mechanical (manual) processing of samples of steel 12Cr18Ni10Ti. On the laboratory bench we assembled, comparative tests are carried out on three methods for processing metal blanks: traditional grinding of samples with a dental diamond head, electrochemical grinding of samples with a dental diamond head and electrochemical grinding of samples with a dental diamond head followed by electrochemical polishing of samples with a round electrode made of wire DKRNM 2.5 L63 (GOST 1066–2015). Images of the surface of samples processed in different ways and the chemical composition of the surface of the sample are obtained on a Hitachi TM4000Plus desktop scanning electron microscope. Measurement of the roughness of the treated surface is carried out on a Model 130 profilometer. Applying an electrochemical grinding method with a diamond head on a metal bond followed by electrochemical polishing with a round electrode eliminates scratches from the diamond head treatment and creates the necessary surface topography to provide a mechanical connection between the metal frame and ceramic. Analysis of the results of comparative studies allows to conclude that the best, in terms of quality, processing efficiency and conditions for providing surface topography, suitable for ensuring a stable mechanical connection between the metal frame and ceramics, is a hybrid processing technology on one processing equipment using diamond electrochemical grinding head on a metal bond, followed by electrochemical polishing with a round electrode. For citation: Borisov M.A., Lobanov D.V., Yanyushkin A.S. Hybrid technology of electrochemical processing of complex profiles. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science , 2019, vol. 21, no. 1, pp. 25–34. doi:10.17212/1994- 6309-2019-21.1-25-34. (In Russian). ______ * Corresponding author Lobanov Dmitry V., D.Sc. (Engineering), Associate Professor I. N. Ulianov Chuvash State University 15 Moskovsky Prospekt, 428015, Cheboksary, Russian Federation Tel. : + 7-908-303-47-45, e-mail : lobanovdv@list.ru