Effect of deformation processing on microstructure and mechanical properties of Ti-42Nb-7Zr alloy

OBRABOTKAMETALLOV Vol. 24 No. 4 2022 216 MATERIAL SCIENCE Effect of deformation processing on microstructure and mechanical properties of Ti-42Nb-7Zr alloy Anna Eroshenko 1, a,*, Elena Legostaeva 1, b, Ivan Glukhov 1, c, Pavel Uvarkin 1, d, Alexey Tolmachev 1, e, Nikita Luginin1, 2, f, Vladimir Bataev 3, g, Ivan Ivanov 3, h, Yurii Sharkeev 1, 2, i 1 Institute of Strength Physics and Materials Science of Siberian Branch Russian Academy of Sciences, 2/4 Akademicheskiy Av., 634055, Tomsk, Russia Federation 2 Tomsk polytechnic university, 30 Lenin Av., 634050, Tomsk, Russia Federation 3 Novosibirsk State Technical University, 20 Prospekt K. Marksa, Novosibirsk, 630073, Russian Federation a https://orcid.org/0000-0001-8812-9287, eroshenko@ispms.ru, b https://orcid.org/0000-0003-3684-9930, lego@ispms.ru, c https://orcid.org/0000-0001-5557-5950, gia@ispms.ru, d https://orcid.org/0000-0003-1169-3765, uvarkin@ispms.ru, e https://orcid.org/0000-0003-4669-8478, tolmach@ispms.ru, f https://orcid.org/0000-0001-6504-8193, nikishek90@gmail.com, g https://orcid.org/0000-0003-1721-2002, bataev@corp.nstu.ru, h https://orcid.org/0000-0001-5021-0098, i.ivanov@corp.nstu.ru, i https://orcid.org/0000-0001-5037-245X, sharkeev@ispms.ru Obrabotka metallov - Metal Working and Material Science Journal homepage: http://journals.nstu.ru/obrabotka_metallov Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science. 2022 vol. 24 no. 4 pp. 206–218 ISSN: 1994-6309 (print) / 2541-819X (online) DOI: 10.17212/1994-6309-2022-24.4-206-218 ART I CLE I NFO Article history: Received: 21 September 2022 Revised: 14 October 2022 Accepted: 03 November 2022 Available online: 15 December 2022 Keywords: Ti-Nb-Zr alloy Severe plastic deformation Ultrafi ne-grained structure Mechanical properties Phase composition Funding The work was performed according to the Government Research Assignment for the Institute of Strength Physics and Materials Science of the Siberian Branch of the Russian Academy of Sciences (ISPMS SB RAS), project No. FWRW-2021-0004 (2021-2024). Experimental research was conducted using the equipment of the Common Use Center “Nanotech” at the Institute of Strength, Physics, and Materials Science, SB RAS (ISPMS SB RAS, Tomsk, Russia). ABSTRACT Introduction. The interest of modern medical materials science is focused on the development of betaalloys of ternary systems (TNZ) based on titanium, niobium and zirconium with the low Young’s modulus, which is comparable with the elastic modulus of the bone. Awide application of the above alloys in medicine is limited by its insuffi ciently high strength properties, such as yield strength, ultimate strength, fatigue strength, fatigue life, etc. The formation of bulk ultrafi ne-grained structure in the alloys via deformation processing, including severe plastic deformation, ensures a considerable increase in the mechanical properties of alloys without toxic alloying elements. The aim of the work is to analyze the infl uence of deformation (multipass rolling and abc-pressing in combination with rolling) on the microstructure and mechanical properties of the alloy of the Ti-Nb-Zr system. The research methods. The Ti-42Nb-7Zr alloy cast blanks were made from pure titanium, niobium, and zirconium iodides by arc melting with a tungsten electrode in the protective argon atmosphere. It is shown that the cast blanks obtained have a high degree of uniformity in the distribution of niobium and zirconium alloying elements. To form an ultrafi ne-grained (UFG) structure, the cast blanks were subjected to deformation according to two schemes: 1) multipass rolling and 2) a combined method of severe plastic deformation, consisting in abc-pressing and subsequent multipass groove rolling. Results and discussion. As a result of deformation processing by rolling, an ultrafi ne-grained (UFG) structure is formed, which is represented by non-equiaxed -subgrains with cross-sectional dimensions 0.2…0.8 μm and length 0.2…0.7 μm, dispersion strengthened nanosized ω-phase, as well as subgrains of the -phase. Application of combined severe plastic deformation has promoted formation of a more dispersed UFG (+ω)-structure with an average size of structural elements equal to 0.3 μm. The UFG structure formed as a result of two-stage SPD has provided a high level of mechanical properties: yield strength – 480 MPa, ultimate strength – 1.100 MPa, microhardness – 2.800 MPa, with a low modulus of elasticity equal to 36 GPa. For citation: Eroshenko A.Yu., Legostaeva E.V., Glukhov I.A., Uvarkin P.V., Tolmachev A.I., Luginin N.A., Bataev V.A., Ivanov I.V., Sharkeev Yu.P. Effect of deformation processing on microstructure and mechanical properties of Ti-42Nb-7Zr alloy. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science, 2022, vol. 24, no. 4, pp. 206–218. DOI: 10.17212/19946309-2022-24.4-206-218. (In Russian). ______ * Corresponding author Eroshenko Anna Yu., Ph.D. (Engineering), Senior Researcher Institute of Physics of Strength and Materials Science, SB of RAS, 2/4 Akademicheskiy Ave. 634055, Tomsk, Russian Federation Tel.: 8 (3822) 28-69-11, e-mail: eroshenko@ispms.ru

RkJQdWJsaXNoZXIy MTk0ODM1