Predicting the high temperature erosion behaviour of materials used in gas turbines

Abstract

The parameters controlling the high temperature erosion process in gas turbines are considered. The oxidation behaviour of the target, temperature, particle loading and particle velocity are shown to be of primary importance. Two regimes are highlighted: oxide modified erosion and substrate dominated erosion. An oxidation model is described which considers the oxide modified erosion regime and applies when the oxide scale thickness is greater than a critical value (the critical oxide thickness). Below the critical oxide thickness erosion occurs principally by surface deformation and substrate removal. A low-cycle fatigue model has been used to predict successfully erosion rates within this regime.