Metallic carbides wetting

Table 7.10. Wetting by Cu of metal-like carbides in a high vacuum at 1100°C(Ramqvist 1965). The equilibrium molar fraction of carbide metal Me dissolved in Cu, X c(Cu), is calculated from equation (7.16). Data for AG (reference state pure liquid metal Me) come from (Rosenqvist 1983) except for Mo2C and HfC (Kubaschewski and Alcock 1979). Data for AHMe(Cu) come from (Niessen et al. 1983).

The good adhesion and wetting observed between Cu and carbides of Mo, W, Cr, Nb and Ta can be explained by considering that metallic bonding can be established at the interface, although covalent and other types of interactions cannot be excluded. More surprising are the experimental results on TiC, ZrC and HfC for which Wa values are several times lower than those found on NbC and TaC, despite a significant DOS at the Fermi level. However, the experimental results in Table 7.10 for TiC, ZrC and HfC are questionable. This appears clearly in the case of TiC and TiN. Indeed, Ramqvist (1965), as well as other authors... 

Table 7.11. Wetting by Cu of non-stoichiometric metal-like carbides in a high vacuum at 1100°C (Ramqvist 1965).

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