Wetting of B4C by molten Ni at 1753 K

The wettability of B4C by molten Ni at 1753 K was investigated using an improved sessile-drop method. The dissolution of B and C into the molten metal cannot promote wettability effectively. The wetting behavior of Ni–B4C can be divided into four stages (i.e., spreading, quasi-stable state, warping and deforming). In spreading stage, the moving of the triple line was controlled by dissolution, and the driving force was the gradient of chemical potential between the liquid and solid interface. In warping stage, the thermodynamic discrepancy of B and C in the liquid led to the formation of a “Hamburger” interface structure. Further, due to the effect of soluto-capillary (i.e., the boron decrease the surface tension around the edge of dissolution zone), B-rich layer induced the warping of dissolution zone edge in apparent.