ABSTRACT
Tungsten has unique physical and chemical properties that make it ideal for high-temperature applications. At room temperature, it is being considered for medical applications due to its protection by an oxide/hydroxide film. However, breakdown of the oxide film and tungsten dissolution can have adverse effects on human health. This study investigates the corrosion of tungsten with and without dispersed oxides of rare-earth elements (ThO2, CeO2, and La2O3) in a 3 wt-% NaCl solution using electrochemical techniques. The results suggest that tungsten dissolution occurs after the formation of an oxide film, likely WO3, on the surface of tungsten and dispersed oxide tungsten. La2O3 and CeO2 may decrease the corrosion rate of tungsten, while WThO2/tungsten has similar corrosion rates to tungsten. The study concludes that CeO2 or La2O3 could replace ThO2 in tungsten due to the radioactive nature of Th.
Acknowledgements
The authors would like to express their gratitude to the CONACYT for providing the equipment necessary to carry out the present study through the infrastructure project under grant 205050. They would also like to thank the National Laboratory for the Study of Nano and Biomaterials (LANNBIO) at CINVESTAV-Mérida for their support. The authors would also like to thank Ing. Gualdemar Casanova for his assistance in the metallographic preparation of the samples.
Disclosure statement
No potential conflict of interest was reported by the author(s).