Influence of cell aspect ratio on architecture and compressive strength of titanium foams

Titanium foams have been of interest in dental and orthopedic implants over the past few decades on account of their excellent mechanical properties, chemical stability, and biocompatibility. A powerful tool, X-ray computed microtomography was used to measure quantitatively the effect of pore morphology on foam architecture. Mechanical properties of titanium foams with varying pore structure were investigated. Aspect ratio of the pores was quantitatively demonstrated to affect strength, degree of anisotropy and strain-rate sensitivity of the produced titanium foams. Needle-like pored foams showed 30–55% lower strength when compared to the foams having lower aspect ratio pores. Lower aspect ratio pored foams were 3–11%, higher aspect ratio pored foams were 17–34% weaker in the direction parallel to the compaction direction when compared to the perpendicular one. High aspect ratio pores also resulted in more pronounced strain-rate sensitivity.