Loadable TiO2 scaffolds—A correlation study between processing parameters, micro CT analysis and mechanical strength

It was shown in the present study that it is possible to produce TiO2 scaffolds with both high mechanical strength and high porosity by using the polymer sponge method. TiO2 scaffolds with porosity above 85% exceeded 1 MPa in compressive strength. TiO2 scaffolds with equally high compressive strength having a fully open porosity close to 90% 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 °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.