Warm congratulations to Keren Shem-tov and Rimma Lapovok for this beautiful joint work to appear in the Journal of the Mechanical Behavior of Biomedical Materials. The message in a nutshell: Indeed SPD confers strength but fatigue resistance is another story….
D. Rittel¹, K. Shemtov-Yona¹, R. Lapovok²
¹ Faculty of Mechanical Engineering, Technion, 32000 Haifa, Israel
² Institute for Frontier Materials, Deakin University, Australia
Severe plastic deformation (SPD) has long been known to confer superior mechanical properties for many metals and alloys. In the general field of biomedical devices in general, and dental implants in particular, the superior strength of SPD-processed commercially pure (CP) titanium, that may surpass that of the stronger Ti6Al4V alloy, has been associated with a superior fatigue resistance. Such a property would make those materials suitable biocompatible and strong alternatives to the currently used titanium alloy.
However, the fatigue characterization reported so far in the literature relies on a very small sample size, thereby precluding any meaningful statistical analysis.
This paper reports and compares systematic fatigue testing of various grades as-received and SPD processed Grade 4 CP-Ti using the recently developed random spectrum loading approach, in both air and 0.9% saline solution.
The results of this study do not support the claim that the SPD process, albeit causing noticeable strengthening, confers any advantage to Grade 4 CP-Ti in terms of fatigue response.