Modelling the behaviour of titanium alloys at high temperature for gas turbine applications

Increased efficiency within the aero engine can be achieved through higher operating temperatures. In order to meet this requirement designers seek either to implement new alloys or show that existing alloys are capable of operating under more extreme conditions. At higher temperatures fatigue is no longer the sole damage mechanism and contributions from creep and environmental interactions must also be considered. This paper seeks to address some of these issues within titanium alloys, and in particular how these high temperature interactions may affect stress concentrations which are often the source of potentially catastrophic fatigue cracks. The requirement to consider both the crack initiation and propagation phase under these conditions is addressed and a modelling capability is presented which shows the ability to predict some of these effects at high temperature. (C) 2010 Elsevier B.V. All rights reserved.