Effect of zirconium on the corrosion behavior of FeAl40Ti3B intermetallic compounds for use in solar water heaters

This study aims to investigate the influence of zirconium addition on the corrosion behavior of the FeAl 40 Ti 3 B intermetallic alloy, which was synthesized in an arc furnace under argon atmosphere at 950 °C for 2 h and subsequently annealed for 168 h at 500 °C in quartz capsules. Electrochemical techniques, specifically potentiodynamic polarization curves and electrochemical impedance spectroscopy measurements (EIS), were employed to assess the corrosion characteristics. The study also delves into the morphological and phase composition changes through scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses. The addition of zirconium to the FeAlTiB alloy led to the formation of zirconium carbide (ZrC) and other phases, including the Laves phase (Fe,Al) 2 Zr. The electrochemical behavior in a 0.5 M H 2 SO 4 solution revealed significant improvements in the corrosion potential ( E corr ), current density ( i corr ), and corrosion rate after the addition of Zr to FeAl 40 Ti 3 B. While the corrosion rate for the unalloyed alloy was primarily diffusion-controlled, the alloy with Zr exhibited charge transfer control. Observations via SEM confirmed the occurrence of pitting corrosion in the FeAl 40 Ti 3 B alloy, but the addition of zirconium substantially enhanced its corrosion resistance. These findings shed light on the positive impact of zirconium addition on the corrosion resistance of the FeAl 40 Ti 3 B alloy, offering valuable insights for potential industrial applications. Graphical abstract