Investigation of selected HVOF and plasma sprayed coatings for sustained performance in molten zinc

Thermal spray coatings, especially WC-12Co, applied on galvanizing line hardware exhibit enhanced corrosion resistance in molten zinc environment. However, the service life of such coated components is usually reported up to 15 days. This work studies 30 days of prolonged performance for coatings like Cr3C2-NiCr, Al2O3, Al2O3-TiO2 and WC-12Co in molten zinc. Post-testing, stability of the coatings was assessed by corrosion products and phase analysis along with elemental mapping, surface morphology and porosity across top and cross sections and weight change data. Property evaluation of these coatings indicates better performance of oxide coatings, particularly Al2O3, as compared to carbide coatings.

Automated summary

This study examines the prolonged performance of coatings like Cr3C2-NiCr, Al2O3, Al2O3-TiO2 and WC-12Co in molten zinc for 30 days, and finds that oxide coatings, particularly Al2O3, exhibit better performance compared to carbide coatings. Post-testing evaluation includes corrosion products and phase analysis, elemental mapping, surface morphology, porosity assessment, and weight change data.