Corrosion Behavior of Hydrotalcite Film on AZ31 Alloy in Simulated Body Fluid

Coatings

Jun Chen¹  Jinqing Ao¹  Sude Ma¹  Kai Kang¹  Yingwei Song²  En-Hou Han² 

[1] Key Laboratory of Fluid and Power Machinery of Ministry of Education, School of Materials Science and Engineering, Xihua University, Chengdu 610039, China;National Engineering Center for Corrosion Control, Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Road, Shenyang 110016, China;

关键词: magnesium alloy;    hydrotalcite film;    simulated body fluid;    corrosion;   

DOI  :  10.3390/coatings9020113

来源: DOAJ

【 摘 要 】

The hydrotalcite (HT) film is a promising bioactive coating for magnesium alloys. In the present study, we investigate the corrosion behavior of HT film in the simulated body fluid (SBF), and compare with which in NaCl solution. The HT film can provide a very plummy initial protection to the AZ31 alloy in SBF. The corrosion behavior of the HT film in the two solutions is quite different. When in 0.1 mol·L⁻¹ NaCl solution, the film is dissolved gradually, and filiform corrosion is predominant after 3 days immersion. While in Hank’s solution, the thickness and composition of the film are changed. A corrosion products layer mainly consisted of Mg/Ca⁻PO₄³⁻/HPO₄²⁻, and minor of CaCO₃ is deposited on the top of HT film, which enhances the barrier effect of the HT film. As a result, except for local pit corrosion at several active places, most of the area of the coated sample still remains integral even after immersion for 15 days. It is demonstrated that the HT film has better corrosion protection effect in SBF than in NaCl solution.

【 授权许可】

Unknown