Vacancy effect on the preparation of high-entropy carbides

Synthesis and mechanical and elevated temperature tribological properties of a novel high-entropy (TiVNbMoW)C 4.375 with carbon stoichiometry deviation

“…Due to the presence of non-stoichiometric carbides, there is a concentration gradient of C, which may reduce the diffusion activation energy required for C atomic diffusion reaction, thereby promoting a C diffusion rate. At the same time, the existence of the carbon vacancy may increase a diffusion rate of metal atoms, and the carbon vacancy effect is applicable to different crystal structures [18].…”

“…In addition, Refs. [18,19] have demonstrated that carbon stoichiometry deviation plays a pivotal role in the formation and densification of the high-entropy transition metal carbides. It has come to light that a synthesis temperature can be reduced due to the increased formation ability, and the densification can be enhanced due to the increased lattice diffusion coefficients [19].…”

Surface energies in high‐entropy carbides with variable carbon stoichiometry

“…[12][13][14][15][16][17][18][19] As we well know, however, the carbon vacancies are quite common in HECs and may have profound effects on physical, chemical, and mechanical properties. [20][21][22][23] Recently, some effort has been made to explore the effects of carbon vacancies on physical, chemical, and mechanical properties of HECs. For example, Malinovskis et al reported that (CrNbTaTiW)C x thin films exhibited enhanced corrosion resistance.…”

“…Therefore, HECs with the diverse properties have been developed by engineering multicomponent metal cations until now 12–19 . As we well know, however, the carbon vacancies are quite common in HECs and may have profound effects on physical, chemical, and mechanical properties 20–23 . Recently, some effort has been made to explore the effects of carbon vacancies on physical, chemical, and mechanical properties of HECs.…”

“…reported a typical hardness evolution in (HfNbTaTiZr)C x thin films as a function of carbon stoichiometry 22 . The sintering temperatures of bulk spark plasma‐sintered HECs with carbon vacancy were reported to be lower than that of HECs without carbon vacancy by He et al 23 . Nevertheless, the current research in this area is still very limited and much more effort should be made to explore this area.…”