Evaluation of arc ion plated NiCoCrAlYSiB coatings after oxidation at 900–1100 °C

NiCoCrAlYSiB coatings were deposited on DS M11 Ni-based superalloys by arc ion plating (AIP). In order to study the effect of Si and B additions on the oxidation behavior of NiCoCrAlY-type coatings, isothermal oxidation tests were carried out from 900 °C to 1100 °C. The results indicated that Si and B additions had little effect on the isothermal oxidation behaviors of coatings at 900 °C and 1000 °C, while the additions improved the oxidation resistance at 1100 °C. The reasons for Si and B improving the oxidation resistance are discussed through analyzing the oxidation kinetics, phase compositions of oxide scales, morphology and elemental distributions through the coatings after oxidation.