This research investigated consecutive multilayer thermal barrier coatings, including Ni 3 Al-Al 2 O 3-Al 2 O 3 /MgO, produced by plasma spray with outer layer thicknesses of 50, 100 and 150 μm deposited on an AISI 316 stainless steel. X-ray diffraction, scanning electron microscopy, Rockwell-B hardness measurements, pin-on-disk wear test and potentiodynamic polarization test were performed to evaluate the specimens. The results revealed that the structure of the produced coatings was completely crystalline. An increase in the coating thickness formed a smooth surface and a low degree of roughness and promoted grain growth. According to the Hall-Petch equation, the degree of hardness decreased from 99 to 92 HRB, and the friction coefficient decreased from 1.25 to 0.6 because of low surface roughness. An adherence test performed with a Brinell hardness test showed that an increase in the layer thickness improved the coating adherence coefficient (d p/dr) from 0.083 to 0.118 kg μm −1. The corrosion test results indicated that the increase in the coating thickness caused a decrease in corrosion current density from 1.1 to 0.008 mA cm −2 .
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.