Hardness prediction of the carbides in Fe-based multi-elements alloy by first-principles

The electronic structures of the carbides such as VC, WC, V 2 C, Mo 2 C, Cr 7 C 3 and Cr 23 C 6 in Fe-based multi-elements alloy were investigated by first principles. According to the bonding characteristics, the different models were adopted to predict the hardness of these carbides, then, which were compared with experimental. The results show that VC, WC, V 2 C, Mo 2 C, Cr 7 C 3 and Cr 23 C 6 are all strong covalent solids and a small metallicity, as well as the contribution of d valence electrons to s - p-d hybridization. Their hardness are 25.80 GPa, 24.28 GPa, 11.52 GPa, 17.06 GPa, 15.07 GPa and 12.78 GPa respectively, which are good agreement with experimental. Graphical abstract