Wetting of carbide ceramics (B4C, SiC, TiC and ZrC) by molten Ni at 1753Â K

Wetting of carbide ceramics (B4C, SiC, TiC and ZrC) by molten Ni was investigated by using an improved sessile drop method at 1753 K. Due to the partial metallic bonds in metallic ceramics (TiC and ZrC), the intrinsic wettability of them is better than the predominantly covalent ceramics (B4C and SiC). The smaller density of solid causes that the dissolution is more incline to the vertical direction, which also causes limited improvement of wettability. The final wettability for specific systems (Ni/carbide ceramic systems) is related to the dissolved solute from substrate, the recrystallized phases and the characteristics of interfacial structures. The spreading dynamics for the dissolutive wetting can be described by molecular dynamic model, and then the main energy barrier for the triple line motion may come from the dissolution.