Titanium alloys containing boron for possible biomedical applications

The service life of metallic prostheses is limited by their failure due to corrosion and/or mechanical overload. Thus, there is ongoing interest in the development of longer lasting bio-implants that can withstand mechanical stresses and potentially deleterious effects in the physiological environment. A new class of titanium alloys is being developed with boron additions that has shown promise for structural applications.  The mechanical properties of these alloys - specific strength and stiffness in particular – increase with boron additions.  However, the effect of these additions on the corrosion resistance of the alloys is only recently being understood. Open circuit potential and cyclic polarization measurements were made in 0.9 wt% NaCl solution for a number of Ti alloys in the as-cast and hot isostatically pressed condition.  In addition, corrosion studies were conducted on thermo-mechanically processed Ti alloys with varying amounts of B.  Key microstructures will be presented in the context of the corrosion data.