The Low-Cycle Fatigue Performance of Emerging Titanium Alloys for Aeroengine Applications

The low-cycle fatigue behavior of three titanium alloys (including two wrought alloys that are commercially available and one under development via a powder sintering technique) is described in order to assess the relative capabilities of a fourth, novel proprietary alloy, designated as RR11. Despite relatively increased levels of beta stabilization, each alloy remains within the general alpha–beta microstructural category and could be considered as an engineering alternative to the well-established Ti-6Al-4V. The relationships between fatigue behavior, microstructure, grain morphology, micro-texture, and alloy chemistry are explored. Emphasis is placed upon the potential cold dwell fatigue sensitivity of the four alternative alloys, which is particularly pertinent since it was recognized that Ti-6Al-4V can suffer from cold dwell-related behavior subject to selected thermo-mechanical processing.