Structure of High-Entropy AlCoCrFeNi Alloy Obtained by Laser Alloying
V. V. Girzhon, V. V. Yemelianchenko, O. V. Smolyakov
Zaporizhzhya National University, 66 Zhukovsky Str., UA-69600 Zaporizhzhya, Ukraine
Received: 07.09.2020; final version - 22.12.2020. Download: PDF
The structural-phase state of the AlCoCrFeNi high-entropy alloy obtained by laser alloying of technically pure aluminium surface layers with a mixture of powders of pure elements Fe, Co, Ni, Cr in an equiatomic ratio is investigated by X-ray phase, X-ray spectral, and metallographic analyses. As shown, in the process of laser alloying the formation of a heterophase structure, which consists of an ordered multicomponent substitution solid solution based on b.c.c. lattice and Al$_{13}$(Ме)$_4$ monoclinic intermetallide, take place. As established, the formation of such a structure is a consequence of melt high cooling rates, high aluminium content and inhomogeneous distribution of chemical components in the surface and bottom layers of the laser alloying zone. The microhardness of the alloyed surface is 4.7 GPa, which is typical for high-entropy alloys of this system obtained by other methods. Additional reasons that may affect the high values of microhardness are analysed.
Key words: high-entropy alloy, laser alloying zone, chemical inhomogeneity, substitution solid solution, high cooling rates, phase composition.
URL: https://mfint.imp.kiev.ua/en/abstract/v43/i03/0399.html
DOI: https://doi.org/10.15407/mfint.43.03.0399
PACS: 61.80.Ba, 62.20.Qp, 64.60.My, 81.20.Vj, 81.40.Gh
Citation: V. V. Girzhon, V. V. Yemelianchenko, and O. V. Smolyakov, Structure of High-Entropy AlCoCrFeNi Alloy Obtained by Laser Alloying, Metallofiz. Noveishie Tekhnol., 43, No. 3: 399—406 (2021)