Fabrication of titanium dioxide ceramics by laser sintering green layers prepared via aerosol assisted spray deposition

Titanium dioxide powder films with controllable microstructures were prepared using aerosol assisted spray deposition under an electric field, and then utilized as the green layers for subsequent selective laser densification to obtain titanium dioxide ceramics. The processing parameters of aerosol assisted spraying include deposition temperature and precursor concentration. The effects of changes to these parameters were studied and discussed with regard the production of desirable films. With optimised parameters, aerosol assisted spray deposition can be used to prepare uniform, smooth, and porous titanium dioxide films which are suitable green layers for laser densification. The effects of the processing parameters of laser densification including laser scanning speed, laser beam size and laser power on the microstructural development and phase transition of the films were investigated and discussed. Dense titanium dioxide ceramics have been generated through the laser densification of the titanium dioxide powder films. The fully automated solid freeform fabrication of three-dimensional ceramic components could be realized through a layer-by-layer process using the laser-assisted fabrication.