The effect of heat treatment and HCF performance on hydrogen trapping mechanism in Timetal LCB alloy

Metastable β titanium alloys provide an advantageous balance of mechanical properties compared to other titanium alloys. Recently, a metastable low cost beta (LCB) Ti-based alloy has been developed by TIMET to be used as a high performance substitute for more classical materials in new non-aerospace technologies and has been marketed primarily for coil spring applications. However, in many of these technological applications, problems may arise when hydrogen comes in contact with titanium-based alloys. The main objective of this research is to investigate the combined influence of hydrogen and high cycle fatigue (HCF) performance on hydrogen's trapping mechanisms, microstructure and microhardness of a heat-treated Ti–6.8Mo–4.5Fe–1.5Al (Timetal LCB).Thermal desorption spectroscopy, supported by other experimental techniques such as X-ray diffraction, scanning and transmission electron microscopy, and microhardness tests, is used to determine the desorption characteristics and trapping parameters.