Corrosion Resistance of Zr as Metallic Biomaterials

Abstract

The corrosion behavior of Zr and Zr-based binary alloys (Zr-Ti, Zr-Nb, Zr-Ta, Zr-Pd, Zr-Pt, Zr-Cu, and Zr-Au) with various concentrations in simulated body fluids were investigated. Pure Zr showed pitting corrosion during the potentiodynamic anodic polarization measurement in Hanks' solution, however, the pitting potential of Zr was much higher than that of type 316L stainless steel. The pitting potential was widely changed by the composition of the alloy. In particular, Zr alloyed with larger amount of Ti, Nb, and Au showed higher pitting potential than pure Zr. Thus, these alloying elements can be considered as beneficial for improving corrosion resistance in physiological environment. On the other hand, Zr-Cu alloys showed low pitting potentials. Therefore, Zr alloys should be carefully designed when they will be used in chloride-containing environments.