Preparation of Controllable Porous Ti–Al Materials with Zn Space Holders

Porous Ti–Al intermetallic compounds were successfully fabricated through powder metallurgy process with Zn as space holders. The influence of Al content and cold compacting pressure on samples of microstructure, phase identification, expansion behavior, open porosity and density were investigated. The results show that Ti–3 wt% Al alloy possessed high open porosity (55.47%) and exhibited three-dimensional connected pore channels. Therefore, the research placed emphasis on the Ti–63 wt% Al with 20 vol.% Zn at different cold compacting pressure. It was found that in the presence of Zn, the morphology of products changed from irregular round spheres to laminated shape, but the phase composition always remained as a single Al 3 Ti phase. Furthermore, the volume expansion rate increased continuously with the increase in cold compacting pressure, and the axial, radial expansion rate also followed the same law. The open porosity of porous materials and the initial density of green billet also increased, reaching 76.74% and 3.52 g cm −3 , respectively, but the density of samples after sintering showed a linear decreasing trend, with the lowest being only 0.89 g cm −3 .