NaCl was expected to be the ideal m

NaCl was expected to be the ideal material to be LPSed during UCS as (i) it has a high water solubility which increases the equilibrium grain boundary liquid film thickness during sintering (Eq. (17)), (ii) it has quite a large diffusion coefficient in water and (iii) it is strongly hydrophilic thus eventually promoting the formation of a brine that might sustain LPS. Even in this ideal case, however, the experimental results appear inconsistent with LPS densification. Recalling the studies by Kingery et al. [41] on pressure-assisted consolidation of NaCl in the presence of water, the authors concluded that although LPS cannot be completely ruled out, a pivotal role on densification is played by plastic flow, which appears strongly accelerated by the presence of water. Therefore, our theoretical results appear consistent with the experimental observations in the literature.