OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 24 No. 4 2022 Residual stress estimation in crystalline phases of high-entropy alloys of the AlxCoCrFeNi system Ivan Ivanov 1, a, *, Aleksandr Yurgin 1, b, Igor Nasennik1, с, Konstantin Kuper2, 3, d 1 Novosibirsk State Technical University, 20 Prospekt K. Marksa, Novosibirsk, 630073, Russian Federation 2 Budker Institute of Nuclear Physics of the Siberian Branch of the RAS, 11, Ac. Lavrentieva ave., Novosibirsk, 630090, Russian Federation 3 Federal Research Center Boreskov Institute of Catalysis, 11, Ac. Nicolskiy ave., Koltsovo, 630559, Russian Federation a https://orcid.org/0000-0001-5021-0098, i.ivanov@corp.nstu.ru, b https://orcid.org/0000-0003-0473-7627, yurgin2012@yandex.ru, с https://orcid.org/0000-0003-0937-5004, goga.mer@mail.ru, d https://orcid.org/0000-0001-5017-6248, k.e.kuper@inp.nsk.su 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. 181–191 ISSN: 1994-6309 (print) / 2541-819X (online) DOI: 10.17212/1994-6309-2022-24.4-181-191 ART I CLE I NFO Article history: Received: 13 September 2022 Revised: 26 September 2022 Accepted: 06 October 2022 Available online: 15 December 2022 Keywords: High-entropy alloys AlxCoCrFeNi Plastic deformation Residual stresses Synchrotron X-ray diffraction Funding This study was funded according to Russian Science Foundation research project № 20-73-10215 “In-situ study of the evolution of the dislocation structure of plastically deformed highentropy alloys under high-pressures and temperatures using synchrotron radiation”. Research was conducted at core facility “Structure, mechanical and physical properties of materials”. ABSTRACT Introduction. All plastically deformed alloys are characterized by crystal defects that increase the internal energy of the system. These defects also result in residual stresses that have a complex effect on the material properties. Macrostresses are often the most critical and can lead to warpage, reduced corrosion resistance, and changes in material strength characteristics. The purpose of this work is to assess the residual stresses of the primitive cubic phase of high entropy alloys Al0.6CoCrFeNi and AlCoCrFeNi. Research methods. The crystal structure of the alloys is studied using the method of X-ray diffraction analysis. Experiments on X-ray diffraction analysis were carried out at the Siberian Center for Synchrotron and Terahertz Radiation on a VEPP-4 (Novosibirsk, INF SB RAS, 5-A line «X-ray microscopy and tomography»). Studies using synchrotron radiation were carried out in the transmission mode. The evaluation of the residual macrostresses of the crystalline phases of the alloys was based on the analysis of the change in the shape of the diffraction rings with a change in the azimuth angle (χ). Materials. The objects of research are ingots of high-entropy alloys Al0.6CoCrFeNi and AlCoCrFeNi. The ingots were obtained from pure metals by argon arc melting with cooling on a copper plate. To conduct further studies, cylindrical samples are cut from the ingots, which were subjected to plastic deformation according to the uniaxial compression scheme. Results and discussion. The obtained results indicate that the Al0.6CoCrFeNi alloy is characterized by higher macrostresses than the AlCoCrFeNi alloy. The residual deformation of the B2 phase lattice of AlCoCrFeNi alloy along the direction [100] is 2.5% at an external load of 2,500 MPa. The distortion value of the lattice of this phase for the alloy Al0.6CoCrFeNi is equal to 5.5% under similar external conditions. In addition, the plastic deformation of the Al0.6CoCrFeNi HEA did not lead to its destruction. This allows concluding that the increased ductility of this alloy is associated not only with the presence of a phase with a FCC lattice, but also with an increased compliance of the phase with a primitive lattice. For citation: Ivanov I.V., Yurgin A.B., Nasennik I.E. Kuper K.E. Residual stress estimation in crystalline phases of high-entropy alloys of the AlxCoCrFeNi system. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science, 2022, vol. 24, no. 4, pp. 181–191. DOI: 10.17212/1994-6309-2022-24.4-181-191. (In Russian). ______ * Corresponding author Ivanov Ivan V., Ph.D. (Engineering) Novosibirsk State Technical University, 20 Prospekt K. Marksa, 630073, Novosibirsk, Russian Federation Tel.: 8 (383) 346-11-71, e-mail: i.ivanov@corp.nstu.ru Introduction High entropy alloys (HEAs) are a new and one of the most promising classes of materials [1–6]. Due to its structure, HEA have high mechanical and physical properties, which make it promising materials for various fi elds.
RkJQdWJsaXNoZXIy MTk0ODM1