Electrophoretically Deposited TiB2 Coatings in NaF-AlF3 Melt for Corrosion Resistance in Liquid Zinc

Abstract

Molten salt electrophoretic deposition is a novel method for preparing coatings of transition metal borides such as TiB2, which has emerged in recent years. To broaden the applications of transition metal boride coatings prepared by this method, this paper investigates the corrosion resistance of TiB2 coatings, produced through molten salt electrophoretic deposition, to liquid zinc. By applying a cell voltage of 1.2 V (corresponding to an electric field of 0.6 V/cm) for 1 h in molten NaF-AlF3, the nanoscale TiB2 particles migrated to the cathode and were deposited on the graphite substrate, forming a smooth and dense TiB2 coating with a thickness of 43 μm. Subsequently, after subjecting the TiB2-coated graphite to corrosion resistance tested in molten zinc for 120 h of continuous immersion, no cracks were observed on the surface or within the coating. The produced TiB2 coating demonstrated excellent corrosion resistance. These research results suggest that the fully dense TiB2 coating on the graphite substrate, produced through molten salt electrophoretic deposition, exhibits excellent corrosion resistance to liquid zinc.