1. Effect of Specimen Holder on Static and Fatigue Tests on Titanium/Cement Interfaces

A tension or compression load was applied onto the Ti rod to test the fracture strength and fatigue life of Ti-cement interface under static and fatigue loadings, respectively. These tests are referred as static and fatigue in this study. A customized holder for the cement is required for the static and fatigue experiments, since the typical wedge, pneumatic, or hydraulic gripper are not suitable for static and fatigue tests on the fracture tests of bi-material samples. The objectives of this study are (1) to evaluate the effect of cement thickness on the fracture strength and fatigue life on Ti-cement union by finite element analysis; (2) to evaluate the effect of plastic cement holder and aluminum cement holder on fracture strength and fatigue life on Ti-cement union by experiment and finite element analysis. Ti-cement union model with 0.22 and 0.11 in. cement, Ti-cement-holder union with plastic and aluminum holders were created and validated using ANSYS in this study to develop a suitable specimen holder for static and fatigue tests. Experimental static tests of Ti-cement with both plastic and aluminum specimen holders were conducted as well. The result clearly showed that both plastic and aluminum holders can be used for static test whereas aluminum holder required much larger fracture load compared to the fracture load on plastic holder. Plastic holder is not suitable for fatigue test, because fatigue test required a stronger and more rigid holder such as aluminum.