Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (38권6호 241-247)

Effects of Al and Cr Alloying Elements on the Corrosion Behavior of Fe-Al-Cr Alloy System

Fe-Al-Cr계 합금의 부식거동에 미치는 Al 및 Cr 합금원소의 영향

최한철;
Choe Han-Cheol;

조선대학교 치과재료학교실 및 생체재료나노계면활성화센터;
Department of Dental Materials & Research Center of Nano-Interface Activation for Biomaterials, College of Dentistry, Chosun University;

Abstract

Effects of Al and Cr alloying elements on the corrosion behavior of Fe-Al-Cr alloy system was investigated using potentiodynamic and cyclic potentiodynamic polarization tests(CPPT) in the $H_2SO_4$ and HCI solutions. The corrosion morphologies in Fe-Al-Cr alloy were analysed by utilizing scanning electron microscopy(SEM) and EDX. It was found that the corrosion potential of Fe-20Cr-20Al was highest whereas the critical anodic current density and passive current density were lower than that of the other alloys in 0.1 M $H_2SO_4$ solution. The second anodic peak at 1000 mV disappeared in the case of alloys containing high Al and low Cr contents. Pitting potential increased with increasing Cr content and repassivation potential decreased with decreasing Al content in 0.1 M HCI solution. Fe-Al-Cr alloy containing high Al and Cr contents showed remarkably improved pitting resistance against $Cl^-$ attack from pit morphologies.

Keywords

Fe-Cr-Al Alloy;Potentiodynamic test;CPPT;SEM;EDX;Corrosion;pitting ond repassivation potention;