Mechanical properties of thermally grown submicron oxide layers on a nickel-based superalloy

Abstract Nickel-based superalloys are frequently used under operating conditions that lead to the formation of an oxide layer. In this study, the mechanical properties of such a submicron oxide scale formed on a nickel-based superalloy after oxidation at 650 °C were evaluated. Poisson’s ratio and Young’s modulus of the layered oxide structure were determined to be respectively 0.29, and 259 GPa. Depth-resolved residual stress profiling with nanoscale resolution showed large compressive residual stresses up to 3000 MPa in the oxide, with magnitude correlated to the oxide scale thickness. The relevance of the results to the crack initiation and growth behaviour is discussed.