Characterization of microstructure and passive film difference of FeCrMoCB amorphous coatings affected by feedstock specific surface area

Abstract

Two kinds of FeCrMoCB amorphous coatings were prepared from different specific surface area feedstock. The microstructures of the coatings were characterized utilizing XRD, SEM, microhardness tester, XPS, nanoindentation, etc. Their electrochemical behavior was further studied by electrochemical measurement. The results showed that the coating prepared from the larger specific surface area feedstock showed a denser coating structure with lower porosity. But the coating prepared from smaller specific surface area feedstock had better corrosion resistance. It was found that the reason was mainly due to the influence of the oxidation of feedstock on the wettability of the coating, and the formation mechanism and the properties of the passive films. The coatings prepared from smaller specific surface area feedstock exhibited a superior passive film, manifesting in denser and thicker structures and lower donor density. This is of great significance for the accurate selection of feedstock in the application process to ensure that various coatings can be used to the best of their ability.