Obrabotka Metallov 2020 Vol. 22 No. 2

OBRABOTKAMETALLOV Vol. 22 No. 2 2020 86 MATERIAL SCIENCE Study of the Phase Composition and its Effect on the Mechanical Properties of WC- (Fe-Mn-C) Carbidesteels Irina Sevostyanova 1, 3, a , Tatyana Sablina 1, 3, b , Dmitriy Fedorov 2, c , Aleksandr Golub 2, d , Sergey Kulkov 1, 3, e, * 1 Institute of Strength Physics and Materials Science of the Siberian Branch of the RAS, 2/4, pr. Akademicheskii, Tomsk, 634055, Russian Federation 2 VIRIAL LLC, 27 Engels Avenue, Saint-Petersburg, 194156, Russian Federation 3 National Research Tomsk State University, 36 Lenin Avenue, Tomsk, 634050, Russian Federation a https://orcid.org/0000-0001-6706-6512, sevir@ispms.ru , b https://orcid.org/0000-0002-5941-5732, sabtat@ispms.ru, c https://orcid.org/0000-0003-3327-3868, fedorovdv@virial.ru, d https://orcid.org/0000-0003-3583-3822, dr.sasgol@yandex.ru, e https://orcid.org/0000-0002-4635-6569, kulkov@ispms.ru Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science. 2020 vol. 22 no. 2 pp. 76–88 ISSN: 1994-6309 (print) / 2541-819X (online) DOI: 10.17212/1994-6309-2020-22.2-76-88 Obrabotka metallov - Metal Working and Material Science Journal homepage: http://journals.nstu.ru/obrabotka_metallov ARTICLE INFO Article history : Received: 16 March 2020 Revised: 16 April 2020 Accepted: 02 May 2020 Available online: 15 June 2020 Keywords : Carbide steel Phase Composition Axial compression Hardness Strength Stress Strain Funding The results were obtained in the framework of the Integrated Project “Establishment of import-substituting high-tech full-cycle production of complex-shaped indexable carbide cutting inserts for priority industries” (Agreement No. 075-11-2019- 036 dated November 27, 2019) implemented by the ISPMS SB RAS at the fi nancial support of the Ministry of Education and Science of the Russian Federation as part of Decree of the Government of the Russian Federation No. 218 dated April 09, 2010. ABSTRACT Introduction. For development of new composite materials with high static and dynamic strength a great attention is paid to the binder phase. The usage of steels with structural instability, for example, Fe-Mn-C steels as a binder phase of composites, is a promising direction, due to its high ability to strain hardening and the presence of several martensitic transformations. These materials can provide an effective relaxation of stress concentrators arising near carbide particles in the composite during loading of the material due to free form change in the intercarbide space and transfer the external load to the carbide grains. A number of studies are devoted to such research; however, upon preparation of WC- (Fe-Mn-C) carbidesteels, the elemental composition of the binder phase may change due to the technological features of its manufacture by powder metallurgy methods. Therefore, studying the in fl uence of the manganese content changes in the Fe-Mn-C steel binder on the phase composition and mechanical properties of WC-(Fe-Mn-C) materials is very important. The aim of this work is to study the phase composition and its in fl uence on the mechanical properties of WC- (Fe-Mn-C) carbidesteels with changes of the manganese concentration in the matrix. In this work, WC- (Fe- Mn-C) steels are studied, the manganese content in the binder phase is varied from 4 to 18 wt. %. Materials and methods. Carbidesteels are obtained by impregnation of WC carcass with subsequent quenching in oil from 1150 o C. Studies of carbidesteels in initial state and after axial compression test are carried out using X-ray phase and X-ray diffraction analysis, scanning electron microscopy. Results and discussion . The carbide phase content in the obtained carbidesteels is 82 vol. %, the average grain size of tungsten carbide is 2.4 μ m, while the porosity does not exceed 0.5%. An increase in the manganese content in the binder phase of carbidesteels leads to a change in the phase composition of the binder phase and to an increase in the lattice parameter of austenite. When the binder phase is in a single-phase state, with a manganese content of 8 wt.%, the maximum relative deformation to failure equal to 6.5% is observed. With an increase in the manganese content in the binder phase, the axial compression strength decreases from 4050 to 3500 MPa. Designed carbidesteels can be used as a different kind of tool. The data obtained can be applied in the development of new composite materials with high physical and mechanical properties. For citation: Sevostyanova I.N., Sablina T.Yu., Fedorov D.V., Golub A.V., Kulkov S.N. Study of the phase composition and its effect on the mechanical properties of WC-(Fe-Mn-C) carbide steels. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science , 2020, vol. 22, no. 2, pp. 76–88. DOI: 10.17212/1994-6309-2020-22.2-76-88. (In Russian). ______ * Corresponding author Kulkov Sergey N. , D.Sc. (Physics and Mathematics), Professor Institute of Strength Physics and Materials Science SB RAS 2/4, pr. Akademicheskii, 634055, Tomsk, Russian Federation Tel.: 8 (3822) 286-986, e-mail: kulkov@ispms.ru