Influence of environmental factors on the corrosion-fatigue response of a nickel-based superalloy

Abstract

Nickel disc corrosion is an important area within the gas turbine engine, with the potential to affect the lives of critical rotating parts. To understand the influence of corrosion on such components, it is essential to generate material data in a representative environment; hot corrosion in conjunction with cyclic loading. A comprehensive assessment of the behaviour of alloys U720Li and RR1000 in a laboratory-simulated environment has been undertaken to explore and replicate corrosion-fatigue features that have been identified in service. Key parameters such as salt loading (flux) and variations in mechanical stress cycle have been examined and have shown to modify the corrosion morphology and resulting fatigue life of the material.

This paper is part of a thematic issue on the 9th International Charles Parsons Turbine and Generator Conference. All papers have been revised and extended before publication in Materials Science and Technology.

Keywords

Hot corrosion High temperature corrosion-fatigue Nickel-based superalloys Low-cycle fatigue Mechanical testing Sulphidation Gas tubine engine Power generation

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