Influence of Mechanical Polishing on Cyclic Oxidation Behavior of (Ni,Pt)Al Coatings at 1100°C

This study investigated the effect of polishing on the cyclic oxidation behavior of (Ni,Pt)Al coatings by cyclic oxidation experiment on (Ni,Pt)Al coatings with polishing (P‐(Ni,Pt)Al coatings) and without polishing(O‐(Ni,Pt)Al coatings) at 1100°C. The influence of polishing on oxide phase transformation during the initial oxidation stage and on the rumpling behavior during long‐term cyclic oxidation was evaluated using various techniques, including Raman spectroscopy, microstructural observation, and mass gain measurements. The results indicate that polishing improves the high‐temperature oxidation resistance of (Ni,Pt)Al coating. This enhancement is attributed to the high density of defects introduced during the polishing process, which promotes the rapid transformation of θ‐Al 2 O 3 to α‐Al 2 O 3 in the P‐(Ni,Pt)Al coating. The current work provides valuable guidance for the surface treatment of (Ni,Pt)Al coatings.