The Role of Oxygen in α

The mechanical and microstructural response of a model Ti-7wt.%Al alloy doped with 500 wppm oxygen has been examined in detail as a function of ageing. Three ageing conditions, ice-water quenched, and aged at 550 oC for 10 or 49 days were examined in detail as a function of ageing. Nanoindentation was used to measure hardness as a function of ageing, while Atom Probe Tomography (APT) also revealed α2 precipitation in the aged samples. The partitioning pReference of oxygen to the α matrix instead of the α2 precipitates has been directly measured