Obrabotka Metallov 2018 Vol. 20 No. 2

OBRABOTKAMETALLOV Vol. 20 No. 2 2018 72 MATERIAL SCIENCE References 1. Polmear I.J. Light alloys: from traditional alloys to nanocrystals . Amsterdam, Elsevier Ltd, 2005. 2. Kolachev B.A. Vodorod vmetallakh i splavakh [Hydrogen inmetals and alloys]. Metallovedenie i termicheskaya obrabotka metallov = Metal Science and Heat Treatment , 1999, no. 3, pp. 3–11. (In Russian). 3. Hess P.D., Tumbull G.K. Effects of hydrogen on properties of aluminum alloys. Hydrogen in Metals . American Society for Metals. Metals Park, Ohio, ASM, 1974, pp. 277–287. 4. Talbot D.E.J. Effects of hydrogen in aluminum, magnesium, copper, and their alloys. International Metallurgical Reviews , 1975, vol. 20, pp. 166–184. On the Participation of Hydrogen in the Formation of the Properties of Hypereutectic Al-Si Alloys Vladimir Afanas’ev a , Marina Popova b, * , Marina Malyuh c , Svetlana Dolgova d Siberian State Industrial University, 42 Kirov str., Novokuznetsk, 654007, Russian Federation a https://orcid.org/0000-0003-0178-5471, in_afanaseva@mail.ru , b https://orcid.org/0000-0001-8010-9134, m.popova@rdtc.ru, c https://orcid.org/0000-0003-2299-9292, starostina_ma1976@mail.ru , d https://orcid.org/0000-0002-8044-196X , sv_dolgov@mail.ru Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science. 2018 vol. 20 no. 2 pp. 63–74 ISSN: 1994-6309 (print) / 2541-819X (online) DOI: 10.17212/1994-6309-2018-20.2-63-74 ARTICLE INFO Article history : Received: 02 February 2018 Revised: 26 February 2018 Accepted: 17 March 2018 Available online: 15 June 2018 Keywords : Al-Si alloys Hydrogen The crystals of primary silicon Crystallization Deformation Temperature coefficient of linear expansion ABSTRACT Introduction. Aluminum alloys of special purpose are characterized by a certain combination of mechanical, physical, and physical-chemical properties due to operation under strictly defined conditions. In the development of new materials with improved technological properties, much attention is paid to alloys of the Al-Si system of hypereutectic concentration. It is known that the combined modifying agent comprising 2 or more elements outperform each component separately. A large number of ways to modify these alloys with the purpose of grinding the primary silicon crystals and eutectic is developed. Most known technologies are not widely applied in practice, therefore, the development of a method for modifying the melt of hydrogen-containing compounds remains a topical theme. Objective: development of technological method of processing the melt, providing for an increase of hydrogen content, for modifying the structure of the as-cast and obtaining the deformed Al – 15...30 % Si alloys with improved physical and mechanical properties. The parameters of the microstructure in the cast state and after the hot plastic deformation, as well as the mechanical characteristics of the modified alloys, are investigated . The study of the microstructure of the resulting alloys is undertaken. Research methods. Dilatometric tests, mechanical tests for static elongation, as well as metallographic analysis of the investigated alloys are used. The results and discussion. A new method of modification that allows reducing sharply the size of the primary crystals of the siliceous phase, resulting in greatly increased mechanical properties of high-silicon alloys and its deformability is suggested. Application of the developed method allows obtaining the structure of the eutectic type in hypereutectic Al-Si alloys. By obtaining the modified structure, characterized by an increased degree of dispersion of the constituents, a sharp decrease in the dimensions of the primary crystals of the brittle siliceous phase and a favorable change in its shape, plastic deformation of the investigated alloys became possible. It is found that hot deformation has a positive effect on the mechanical properties of Al-Si alloys, especially on its plasticity. It is shown that the complex of physical- chemical properties of deformed semi-finished products exceeds even the properties of sintered aluminum alloys. For citation: Afanas’ev V.K., Popova M.V., Malyuh M.A., Dolgova S.V. On the participation of hydrogen in the formation of the properties of hypereutectic Al-Si alloys. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science , 2018, vol. 20, no. 2, pp. 63–74. doi: 10.17212/1994-6309-2018-20.2-63-74. (In Russian). ______ * Corresponding author Popova Marina V. , D .Sc. (Engineering), Associate Professor Siberian State Industrial University, 42 Kirov str., Novokuznetsk, 654007, Russian Federation Тел.: 8 (384) 346-32-91, e-mail: m.popova@rdtc.ru Obrabotka metallov - Metal Working and Material Science Journal homepage: http://journals.nstu.ru/obrabotka_metallov