Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (39권1호 18-24)

Critical Pitting Temperature of 2205 Duplex Stainless Steels Using Immersion and Electrochemical Polarization Test Methods

침지시험법 및 전기화학적 분극법에 의한 2205 이상 스테인리스강의 임계공식온도 측정 비교

신재호;이재봉;
Shin Jae-Ho;Lee Jae-Bong;

국민대학교 신소재공학부;
School of Advanced Materials Engineering, Kookmin University;

Abstract

Although stainless steels have the excellent corrosion resistance by passive film, they are susceptible to pitting corrosion in the environment containing halogen elements such as chloride ions. The resistance to pitting corrosion can be evaluated by measuring the critical pitting temperature (CPT). CPT values can be obtained using immersion, potentiodynamic and potentiostatic polarization test methods. Results on duplex 2205 stainless steels showed that CPT values were measured as $50^{circ}C,;55^{circ}C;and;61^{circ}C$, respectively for immersion, potentiodynamic and potentiostatic polarization test methods, depending upon the different test methods, even though the difference between CPT values are not much.

Keywords

Critical pitting temperature;Immersion test;Potentiostatic polarization;Potentiodynamic polarization;Pitting resistance equivalent index;Pitting potential;