High Temperature Alloys for the Gas Turbine - The State of the Art

Reviewed in this paper are recent achievements in the development of materials for 1200–2200 F service in the gas turbine. These include advances in creep strength of turbine disc alloys and the significance of low cycle fatigue to new disc materials, and the recent developments in wrought and cast turbine blading alloys, with discussions of sulfidation and thermal fatigue. The importance of chromium relative to corrosion resistance and the value of diffusion coatings as an alternative to built-in protection are evaluated. Finally, wrought alloys for hot ducting structures and the outlook for dispersion strengthened alloys are discussed.