Preparation conditions and porosity of porous titanium sintered under positive pressure

Different with vacuum powder sintering technique, the porous titanium has been sintered under positive pressure (<0.1 MPa, GP) in argon atmosphere. Using high purity titanium powder as raw material, the preparation conditions affecting porosity have been studied. The results show that pore-forming agent can be removed by heat treatment at 350°C. The porosity decreases with the increasing of sintering temperature and holding time. When the holding time prolongs from 1 h to 4 h, the porosity reduces 3.3%. The porosity decreases with the increasing of molding pressure, and it is a nearly linear relationship when the molding pressure <230 MPa. The pore porosity of samples can reach to 63.7% (open-pore porosity >60%) with the pore-forming agent content 50 wt%. The pore size of porous titanium shows multipeak distribution, and the distribution can be controlled in a narrow range. Furthermore, the porous titanium performed well mechanical strength with plateau stress of 185 MPa.