Synthesis, crystal structure, and properties of stoichiometric hard tungsten tetraboride, WB4

Bykova E, Ovsyannikov S, Bykov M, Yin Y, Fedotenko T, Holz H, Gabel S, Merle B, Chariton S, Prakapenka VB, Dubrovinskaia N, Goncharov AF, Dubrovinsky L (2022)

Publication Type: Journal article

Publication year: 2022

Journal

Journal of Materials Chemistry A Royal Society of Chemistry

DOI: 10.1039/d2ta02268k

Abstract

Tungsten tetraboride has been known so far as a non-stoichiometric compound with a variable composition (e.g. WB4-x, WB4+x). Its mechanical properties could exceed those of hard tungsten carbide, which is widely used nowadays in science and technology. The existence of stoichiometric WB4 has not been proven yet, and its structure and crystal chemistry remain debatable to date. Here we report the synthesis of single crystals of the stoichiometric WB4 phase under high-pressure high-temperature conditions. The crystal structure of WB4 was determined using synchrotron single-crystal X-ray diffraction. In situ high-pressure compressibility measurements show that the bulk modulus of WB4 is 238.6(2) GPa for B ' = 5.6(0). Measurements of mechanical properties of bulk polycrystalline sub-millimeter size samples under ambient conditions reveal a hardness of similar to 36 GPa, confirming that the material falls in the category of superhard materials.

Authors with CRIS profile

Stefan Gabel Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften)

Involved external institutions

Universität Bayreuth DE Germany (DE) Universität zu Köln DE Germany (DE) Deutsches Elektronen-Synchrotron DESY DE Germany (DE) Universität Kassel DE Germany (DE) University of Chicago US United States (USA) (US) Carnegie Institution for Science US United States (USA) (US)

How to cite

APA:

Bykova, E., Ovsyannikov, S., Bykov, M., Yin, Y., Fedotenko, T., Holz, H.,... Dubrovinsky, L. (2022). Synthesis, crystal structure, and properties of stoichiometric hard tungsten tetraboride, WB4. Journal of Materials Chemistry A. https://dx.doi.org/10.1039/d2ta02268k

MLA:

Bykova, Elena, et al. "Synthesis, crystal structure, and properties of stoichiometric hard tungsten tetraboride, WB4." Journal of Materials Chemistry A (2022).

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