National Research Nuclear University MEPhI, Moscow, Russia

О. А. Krymskaya, Associate Professor, Candidate of Sciences in Physics and Mathematics, e-mail: OAKrymskay@mephi.ru
М. G. Isaenkova, Professor, Doctor of Sciences in Physics and Mathematics, e-mail: MGIsaenkova@mephi.ru
I. А. Cherepanova, Master of Science, Engineer, e-mail: irinacherepanova12@yandex.ru
А. V. Osintsev, Associate Professor, Candidate of Technical Sciences, e-mail: AVOsintsev@mephi.ru

Nickel alloys are characterized by high heat resistance and heat strength, which ensures their wide application in various fields of industry. A promising technology for producing complex-shaped structural elements from nickel alloys is selective laser powder melting (SLM). In this work, the structural-phase state, texture and mechanical properties of samples from EP648 alloy prepared using the SLM method are analyzed. X-ray and synchrotron methods of study were used to analyze the structure; mechanical tensile tests were carried out on samples cut along and perpendicular to the track direction. It is shown that EP648 alloy is a matrix of the face-centered cubic phase (γ-phase) strengthened by an additional carbide phase Me23C6. Regularities in the formation of crystallographic texture during SLM of EP648 alloy powder are established. The influence of the laser beam scanning strategy in powder SLM on the structure, crystallographic texture, macrostresses and mechanical properties of samples made of EP648 alloy powder is revealed. The Young’s modulus and Taylor factor calculated from the texture, as well as the anisotropy of mechanical properties are compared with the results obtained in tensile testing of samples. The calculation results are in agreement with the experimental data on the anisotropy of strength and plastic properties of nickel alloys, which allows using the calculation of properties from the crystallographic texture to predict the behavior of materials under operating conditions.
V. A. Fesenko, a researcher of the National Research Nuclear University MEPhI, was actively involved in the work.
The work was carried out with the financial support of the Russian Federation represented by the Ministry of Science and Higher Education of the Russian Federation (Agreement No. 075-15-2021-1352).

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