Stability of TiB2-C composite coatings

Several recipes of pitch-bonded TiB2 were studied with respect to adherence, cracking and stability during electrolysis. A successful recipe for a crack-free coating was obtained. The coating showed good adherence and stability after 34 hours of electrolysis. The wetting of the coating by aluminium in the presence of cryolite melt was time dependent and almost complete wetting was observed after 120 minutes. Furan resin-based TiB2 coatings were not wetted by aluminium during electrolysis due to the presence of a carbon layer at the coating surface. Coating samples were polished by SiC paper after curing. The polished samples showed good stability and aluminium wetting.