Exploring the elastic and electronic properties of chromium molybdenum diboride alloys

JOURNAL OF ALLOYS AND COMPOUNDS

卷:866

Article

Dovale-Farelo, Viviana¹  Tavadze, Pedram¹  Verstraete, Matthieu J.^2,3,4  Bautista-Hernandez, Alejandro⁵  Romero, Aldo H.^1,5 

[1] West Virginia Univ, Dept Phys, Morgantown, WV 26506 USA

[2] Univ Liege, NanoMat Q Mat CESAM, B5, B-4000 Liege, Belgium

[3] Univ Liege, European Theoret Spect Facil, B5, B-4000 Liege, Belgium

[4] Catalan Inst Nanosci & Nanotechnol ICN2, Campus UAB, Barcelona 08193, Spain

[5] Benemerita Univ Autonoma Puebla, Fac Ingn, Edificio ING2,Ciudad Univ, Puebla 72570, Mexico

关键词: High-temperature alloys;    Transition metal alloys and compounds;    Crystal structure;    Electronic properties;    Heat capacity;    Mechanical properties;    Phonons;    Thermal expansion;    Thermodynamic properties;    Ab initio calculations;   

DOI  :  10.1016/j.jallcom.2021.158885

来源: Elsevier

【 摘 要 】

We perform first-principles calculations to study the structural, mechanical, thermal, electronic, and magnetic properties of Cr1-xMoxB2 for x = 0.25, 0.33, 0.50, 0.67 and 0.75. Based on structural search methods, we determine the ground-state structure for each concentration. The ternaries are either monoclinic (x = 0.25, 0.75) or trigonal (x = 0.33, 0.50, 0.67). The calculated mechanical properties reveal that the strength of Cr1-xMoxB2 is maximized for x = 0.50. Cr0.5Mo0.5B2 exhibits excellent mechanical properties (B = 298 GPa, Y = 558 GPa, G = 235 Gpa, nu = 0.19, H-v =27 GPa), surpassing those of beta-MoB2 at a lower cost. All of these ternaries are hard alloys with Vickers hardness greater than 24 GPa. Chemical bonding analysis demonstrates that the strength of the new compounds is related to the alternating planar and buckled B-B layers, as well as the strong TM-B bonds. The enhanced strength of Cr0.5Mo0.5B2 is a consequence of the high density of strong interlayer Cr-Mo metallic bonds around the Fermi level. (C) 2021 Elsevier B.V. All rights reserved.

【 授权许可】

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