Stellite alloys are primarily preferred in various component manufacturing
industries due to its magnificent mechanical and electrochemical properties.
The stellite powder is deposited over the materials by Various thermal spray
methods in industries. This research proposed investigating the
microstructure and corrosion properties of stellite powder that is deposited
on an AZ91D magnesium alloy substrate by atmospheric plasma spraying
process. SEM, optical microscopy, and atomic force microscopy are typical of
the coatings. Immersion experiments in sodium chloride conditions are
conducted at varying pH levels, chloride ion concentration, and exposure
time. In addition, XRD examined the phase change properties of the powder
and sprayed condition of coatings along with corrosion testing. The
corrosion experiments were conducted to establish several regression models
based on the central composite design and the response surface process. The
accuracy of the regression models was sufficient to allow correlations
between input parameters and responses through variance analysis. It was
found that the pH value significantly influences the corrosion behaviour of
stellite coatings followed by other parameters such as chloride ion
concentration and exposure time; even in corrosion tests, plasma-sprayed
coatings performed better.
Influence of chloride ion concentration on immersion corrosion behaviour of plasma sprayed alumina coatings on AZ31B magnesium alloy