Microstructural evolution of Ti–6Al–4V during the sintering of microspheres of Ti for orthopedic implants

The sintering of microspheres for porous coating is made in titanium alloys at temperatures close to 1400 °C, thus substantially modifying the microstructure of the bases alloy. This changes is fundamentally due to grain size enlargement and α+β Widmanstaetten structure. Therefore it is necessary to make a deep study of grain growth effect on the hardness of the base material and the component of the sintered balls, in order to evaluate mechanical properties variation due to changes in the microstructure. There are also important complementary stabilization treatments of the microstructure by means of controlled cooling at high speeds it avoids the formation of β phases in grain boundaries, at the same time that avoid the broken-up of the Widmanstaetten structure, developing in an increase in mechanical resistance and fatigue resistance of the prosthesis.