Microstructure formation during laser powder bed fusion of Ti-22Al-25Nb with low and high pre-heating temperatures

•Complete process chain for LPBF of Ti-22Al-25Nb including powder production is considered.•For the first time conventional and high temperature LPBF of Ti-22Al–25Nb is compared.•Characterisation of metastable LPBF conditions by state-of-the-art techniques including high energy synchrotron X-ray diffraction.•Identification of subgrain boundaries and dislocations as preferred nucleation sites of O Phase in the subsurface area.•Phase transformations caused by in-situ and intrinsic heat treatment during high temperature LPBF are revealed.