Effect of rolling direction on mechanical properties of powder-rolled porous titanium plates

Two types of porous titanium plates with the various thicknesses were prepared by powder rolling followed by vacuum sintering in this study, using the hydrogenated dehydrogenated titanium powders as the raw materials. The mechanical properties of the porous titanium plates either perpendicular or paralleled to the rolling direction were studied by the analysis of pore size and pore size distribution, scanning electron microscopy, tension test, three-point bending test, and shearing strengh test, which were also explained from the aspects of pore size distribution and sintering necking development. The results show that, the maximum pore size of the 1.96 mm-thick porous titanium plate is smaller than that of the 1.32 mm-thick plate, while the pore size distributions are relatively uniform. For the powder-rolled porous titanium plates in the same thickness, the average tensile strength and bending strength of the porous titanium plate perpendicular to the rolling direction are 25% and 45% higher than that paralleled to the rolling direction, respectively. With the thickness increasing, the tensile strength, bending strength, and shear strength all rise significantly. It is found that the effect of rolling direction on the mechanical properties of the powder-rolled porous titanium plates exhibits contrary to that of the densified titanium plates.