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Microscopic models of hardness

  • Theory of Hardness and Superhard Materials
  • Production, Structure, Properties
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Abstract

Recent developments in the field of microscopic hardness models have been reviewed. In these models, the theoretical hardness is described as a function of the bond density and bond strength. The bond strength may be characterized by energy gap, reference potential, electron-holding energy or Gibbs free energy, and different expressions of bond strength may lead to different hardness models. In particular, the hardness model based on the chemical bond theory of complex crystals has been introduced in detail. The examples of the hardness calculations of typical crystals, such as spinel Si3N4, stishovite SiO2, B12O2, ReB2, OsB2, RuB2, and PtN2, are presented. These microscopic models of hardness would play an important role in search for new hard materials.

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Original Russian Text © F. Gao, L. Gao, 2010, published in Sverkhtverdye Materialy, 2010, Vol. 32, No. 3, pp. 9–32.

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Gao, F.M., Gao, L.H. Microscopic models of hardness. J. Superhard Mater. 32, 148–166 (2010). https://doi.org/10.3103/S1063457610030020

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