Recent progress on the corrosion behavior of metallic materials in HF solution

Hydrofluoric acid (HF) or fluoride ion corrosion issues are often encountered in many fields, which have attracted extensive research due to its strong corrosiveness. In this paper, a critical review is presented based on recent progress on HF corrosion. In view of the discrepancy of fluoride ion compared with other ions, the special attack characteristics of fluoride ion are firstly discussed. Afterwards, the corrosion mechanisms of stainless steels, nickelbased alloys, and titanium alloys in HF solution or fluoride ion-containing environment are reviewed, and three typical corrosion behaviors are summarized, which are essentially weakening process of passivation of metallic materials. The effects of influencing factors (e.g. alloying elements, environmental factors, and stress, etc.) on HF corrosion are also discussed, which involve changes in passivation mechanism, the influence of HF attack mode and multiple damage mechanisms due tomechanical-chemical coupling. Finally, future research works on HF corrosion are proposed.

Automated summary

This paper provides a critical review on recent progress in HF corrosion, focusing on the special attack characteristics of fluoride ion and corrosion mechanisms of stainless steels, nickel-based alloys, and titanium alloys in HF solution. Three typical corrosion behaviors were summarized, along with a discussion on the effects of influencing factors on HF corrosion. Future research directions on HF corrosion were also proposed.