Adhesion energy in the metal/oxide system for the case of high-temperature oxidation of nickel-based superalloys

Resumo

The microstructure of the oxide layer is studied and the adhesion energy of the metal/oxide interface is determined after high-temperature isothermal oxidation (T = 1150°C) of a single-crystal commercial René N5 nickel alloy. Experiments upon heating and rapid cooling are performed to initiate failure of the oxide layer. The elastic energy of the metal/oxide interface is determined using the model of circular buckling followed by edge delamination. Calculations are conducted for a homogeneous alumina layer and with allowance for the multilayer structure that forms at the initial stages of alloy oxidation. The adhesion energy is 72 and 27 J/m2 for these cases, respectively.