Investigation of the Corrosion Behavior of HVOF-Sprayed Carbide CermetCoatings in Molten Al-Zn-Si Alloy Bath

摘要

In the continuous hot-dip galvanization process, the corrosionand chemical stability of the sink roll in the galvanizing bathare important issues that affect quality and productivity. Inorder to protect the sink roll, carbide cermet and/or ceramiccoatings were deposited on the surface of the sink roll. TheWC-, Cr3C2- cermet coatings were deposited by high velocityoxygen fuel (HVOF) spray, respectively. The coating sampleswere immersed in molten Zn-alloy containing 50wt.%aluminum at 833K for 24 hr and 144 hr, respectively. Theinter-diffusion and inter-reaction of Zn, Al and elements in thecoating and corrosion behavior of these coatings wereinvestigated by XRD, SEM and EPMA, etc. The corrosionmechanisms of the carbide cermet coatings and ceramiccoatings in molten High Al-Zn-alloy were proposed.