An approach to modeling simultaneous high-temperature oxidation and erosion

Abstract

An approach is suggested for describing the rate of degradation of alloys subjected to the combined effects of high-temperature oxidation and erosion. The basis for this approach is essentially empirical, and is drawn from observations of the kinetics and scale morphologies of alloys in laboratory tests. The two major assumptions used are that the alloy surface is always covered by an oxide layer, and that only oxide (not alloy substrate) is removed by the erosion process. The mode of erosion is not explicitly defined. The rate of erosion, that is, the amount of oxide lost in a given erosion event, is taken to be proportional to the thickness of the oxide layer. The relationships developed have been found capable of accurately describing the shapes of oxidationerosion kinetic curves, and the predicted thickness of the steady-state oxide layers remaining on the alloys agreed reasonably with experimental observations.