Corrosion Behavior and Mechanical Properties of Zn–Ti Alloys as Biodegradable Materials

Abstract

The influence of the chemical composition and structural state of Zn–Ti alloys on corrosion behaviour and mechanical properties was studied. Zn-based alloys were investigated, more precisely, pure technical Zn and Zn with 0.10, 0.25 and 1.00 wt.% Ti. The microstructure and chemical composition of these materials were analysed using light optical microscopy (LOM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The chemical composition of the alloys and the surface after immersion were analysed using an EDS detector from Bruker. The alloys’ electro-chemical corrosion resistance was further investigated through linear (LP) and cyclic (CP) potentiometry and open-circuit potential (OCP) analysis. A tensile/compression equipment (Instron 34SC-5) was used to determine the compression behaviour. UMT testing equipment was used to determine microhardness (by Rockwell indentation) and COF vs. length. For percentages higher than 0.25 wt.% Ti, the formation of a primary TiZn16 intermetallic compound in the (α-Zn + TiZn16) eutectic matrix was observed, a slight influence of TiZn16 on the Zn corrosion resistance results, and a greater influence on the mechanical properties was confirmed.

Keywords

• Zn–Ti biodegradable alloy
• corrosion resistance
• degradation rate