Morphological analysis of pores in directionally freeze-cast titanium foams

Synchrotron x-ray tomography was performed on titanium foams with aligned, elongated pores, initially created by sintering directionally freeze-cast preforms using two different powder sizes. Three-dimensional reconstructions of the pore structures were analyzed morphologically using interface shape and interface normal distributions. A smaller powder size leads to more completely sintered titanium walls separating the dendritic pores, which in turn created a more compact distribution of pore shapes as well as stronger pore directionality parallel to the ice growth direction. The distribution of pore shapes is comparable to trabecular bone reported in the literature, indicating the foam's potential as a bone replacement material.