Hot corrosion behaviour of Super 304H for marine applications at elevated temperatures

The aim of this paper is to study the hot corrosion behaviour of super 304H stainless steel for marine applications.

The investigation was carried out with three different combinations of salt mixture (Na₂SO₄, NaCl and V₂O₅) at two different temperatures (800 and 900°C).

The spalling and growth of oxide layer was observed more with the presence of V₂O₅ in the salt mixture at 900°C during experimentation than what was observed in 800°C. The mass change per unit area is calculated to study the corrosion kinetics and also the influence of salt mixture. Further, the samples are analysed through materials characterisation techniques using optical image, scanning electron microscope (SEM), energy dispersive X-ray (EDAX) and X-ray diffraction (XRD) analysis. The presence of V₂O₅ in the salt mixture was the most important influencing species for accelerating hot corrosion.

SEM, EDAX and XRD analysis confirmed the formation of Fe₂O₃ and Cr₂O₃ at 900°C showing contribution in corrosion protection.