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Vickers hardness of Ru-, Ta-, W-, Re-, Os-, and Ir carbides and nitrides calculated by the bond strength method


A bond strength model of Vickers hardness was applied to RuC, TaC, WC, ReC, OsC, IrC, TaN, WN, ReN, OsN, IrN, and Tc2C, Ru2C, Rh2C, Re2C, Os2C, Ir2C crystals. The resulting hardness of transition-metal monocarbides, mononitrides, and subcarbides was found to be within the range of 19–36 GPa. The hardness of these carbides and nitrides has been calculated before by other authors, but these authors incorrectly applied the bond strength method and published erroneous hardness values for all these crystals. Significantly different results and the correct use of the bond strength method are presented in detail.

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We acknowledge CzechNanoLab Research Infrastructure supported by MEYS CR (LM2018110)


Funding was supported by Akademie Věd České Republiky.

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Correspondence to Antonín Šimůnek.

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Šimůnek, A. Vickers hardness of Ru-, Ta-, W-, Re-, Os-, and Ir carbides and nitrides calculated by the bond strength method. MRS Communications (2022).

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  • Hardness
  • Bonding
  • Strength
  • Crystal
  • Predictive
  • Computation