*4.7. The E*ff*ects of Processing Routes on the Evolutions of Texture and Young's Modulus*

In general, the microindentation measurements of Young's modulus E showed moderate changes of E between the IS and all further treatments, being 18 GPa between all materials, and 14 GPa at maximum within the same material. Apart from a general positive offset of the simulated data compared to the measured ones because of an upper-limit calculation, the majority of simulations followed the measured values of E, at least in all cases of HPT-deformation: E slightly increased with increasing torsional strain γ*T*, which increased the intensity of shear texture; the latter (and accordingly also E) reached saturation at highest γ*<sup>T</sup>* where steady state deformation sets in. Thermal treatment, however, should not affect the texture and/or E as long as only recovery processes occur. On the other hand, recrystallization processes must be involved when E changes during thermal treatment, and when this change is also reflected in the simulation, like in the cases of (IS and heat-treated) samples

shown in Figure 15. When the simulation does not follow the measured change of E during thermal treatment (e.g., as seen during long-time thermal treatment of HPT 0.5 rot sample) we must suppose the thermally-induced formation of a new phase which is perhaps not registered by XRD due to its small volume fraction. At this point, we conclude the discussion because, as already mentioned, the measured variations in E did not exceed 50 GPa which is still close to that of bone (E = 10–30 GPa) [72]; thus the requirements to avoid the stress-shielding effect [1] in implant applications were still fulfilled.
