Journal of the Korean institute of surface engineering (한국표면공학회지)

The Korean Institute of Surface Engineering (한국표면공학회)
권호 표지

Corrosion of Zn and Zn-Fe alloys in $Ca(OH)_2$ Solutions

$Ca(OH)_2$ 수용액에서 Zn과 Zn-Fe 합금의 부식

  • Lee, Soo-Sun (Department of Materials Engineering, College of Engineering, Hanyang University) ;
  • Kang Sung-Goon (Department of Materials Engineering, College of Engineering, Hanyang University)
  • 이수선 (한양대학교 공과대학 재료공학과) ;
  • 강성군 (한양대학교 공과대학 재료공학과)
  • Published : 1986.12.01
Download PDF
⟨ Previous Next ⟩

Abstract

The effects of alternating voltage, $Cl^-$ ion and pH on the corrosion of Zn and Zn-Fe alloys have been investigated by using electrochemical techniques in $Ca(OH)_2$ solutions. The passive film $Zn(OH)_2$ was initially formed on the Zn surface and gradually transformed to $Ca(Zn(OH)_3)_2{\cdot}2H_2O$, which was identified with the X-ray diffraction method, SEM micrograph and EPMA. The passivity current increased with increasing alternating voltage and decrease AC frequency. ${\xi}$ phase in Zn-Fe alloys reduced the effects of AC. The effect of $Cl^-$ ion on the passivity current of Zn was similar to the AC effect, resulting in pits on Zn. It was also found that the passive region of Zn decreased rapidly below pH 10.3 of the solution.

Keywords