The effect of surface machining on the high-temperature oxidation of a single crystal Ni-based superalloy

Abstract

Single crystal samples were subjected to different surface compressive finishing conditions on [001] oriented surfaces. The initial surface residual compressive stresses were determined to be 901, 635 and 0 MPa, respectively. Isothermal oxidation in ambient atmosphere at 1573 and 1273 K resulted in a reduction of oxide scale thickness and a change of primary oxides from nickel oxide to alumina on deformed surface. Such result can be attributed to the increased diffusivity of aluminum beneath the deformed surface at high temperatures.