Influence of position and laser power on thermal history and microstructure of direct laser fabricated Ti-6Al-4V samples

A finite element model has been established and used to predict the temperature history of direct laser fabricated (DLFed) Ti-6Al-4V thin wall samples. The effects of laser power and the effect of location within a sample on its temperature history have been modelled and compared with temperatures measured during DLF using thermocouples. The thermal history of the material has been correlated with the observed differences in the microstructures obtained at different locations in a given sample or for a given location in samples obtained at different laser powers.