Superior Corrosion Resistance of Ti-Al-Zr Alloy in Aggressive Nitric Acid Environments

Influence of Oxygen-Enriched Layer on the Passivity of Ti-Al-Zr Alloy in an Alkaline Environment

“…50 The authors have also studied the behavior of the same alloy, Ti-Al-Zr, in nitric acid and reported a similar behavior of increased anodic current density at higher potentials under different experimental conditions. 29 Thus, based on the result and existing literature, it can be inferred that at potential higher than 0.9 V Ag/AgCl , a new passive layer would have formed on the surface of Ti-Al-Zr electrode for all oxidized conditions. As discussed later, the passive film composition was identical for the specimens of Ti-Al-Zr hence a similar E tr value was observed (Table I).…”

“…Similar behavior of other titanium alloys at higher potentials (greater than 1 V Ag/AgCl ) has been reported by other investigators in different aqueous media. 29,[50][51][52] Ghasemi et al 50 studied the behavior of Ti-6Al-4V in phosphate buffer saline solution at room temperature. They reported an increase in anodic current density beyond 1.5 V Ag/AgCl and attributed the phenomena to the formation of a new passive layer made of phosphorus-containing titanium complex.…”

“…It has been reported by the authors that the material has a superior corrosion resistance than SS 304 L in aggressive nitric acid environments. 29 The authors have proposed Ti-Al-Zr as a candidate structural material for the reprocessing plant handling a nitric acid environment. 29 The possibility of using the alloy in an alkaline environment is also to be investigated especially when the material has an oxygen-enriched layer on the surface.…”

“…29 The authors have proposed Ti-Al-Zr as a candidate structural material for the reprocessing plant handling a nitric acid environment. 29 The possibility of using the alloy in an alkaline environment is also to be investigated especially when the material has an oxygen-enriched layer on the surface. To achieve this objective, the material was exposed in the air at 760 °C for different durations that led to the formation of an oxide layer on the surface and an "alpha-case" beneath the oxide layer.…”