Loadable TiO_2 scaffolds--A correlation study between processing parameters, micro CT analysis and mechanical strength

摘要

It was shown in the present study that it is possible to produce TiO_2 scaffolds with both high mechanical strength and high porosity by using the polymer sponge method. TiO_2 scaffolds with porosity above 85 percent exceeded 1 MPa in compressive strength. TiO_2 scaffolds with equally high compressive strength having a fully open porosity close to 90 percent is not previously been reported in the literature. Reduction of porosity leads to even further reinforce the scaffolds' mechanical structure. A statistical correlation study with 160 tested scaffolds defined the most important manufacturing steps and the governing morphological characteristics for the scaffold's increased mechanical strength. The key manufacturing factors were a holding phase during sintering time for more than 30 h (at 1500 deg C) and multiple coatings of the scaffold's structure. The crucial parameters for high mechanical strength were the fractal dimensions of the struts, object surface/volume ratio, density and overall porosity.