The corrosion behavior of HVOF TiAlNb coating in molten Zn-0.2 wt.% Al

Abstract

Abstract In order to understand the corrosion behavior of high-velocity oxygen-fuel (HVOF) TiAlNb coatings in molten Zn-0.2 wt.% Al, the different kinds of TiAlNb coating were deposited on 316L stainless steel substrate and the corrosion tests in molten zinc were carried out. The coating morphologies, phase composition, and characteristics of HVOF TiAlNb coatings at different stages of immersion time were studied by means of scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy-dispersive X-ray spectrometry (EDX). The results indicated that the HVOF sprayed TiAlNb intermetallic compound coatings have excellent corrosion resistance to molten zinc. The corrosion type of the HVOF TiAlNb coatings in molten Zn-0.2 wt.% Al is pitting corrosion and crack corrosion. In the whole corrosion stage of molten Zn-0.2 wt.% Al, the corrosion time has no effect on the phase compositions of the HVOF TiAlNb coatings.