Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (50권5호 366-372)

Characteristics of Coating Films on Hot-Dipped Aluminized Steel Formed by Plasma Electrolytic Oxidation Process at Different Current Densities

PEO 전류밀도 조건에 따른 알루미늄도금 강재상 산화코팅막의 특성

최인혜;이훈성;이명훈;
Choi, In-Hye;Lee, Hoon-Seung;Lee, Myeong-Hoon;

한국해양대학교 기관공학부;
Division of Marine Engineering, Korea Maritime and ocean University;

DOI : 10.5695/JKISE.2017.50.5.366

Abstract

Plasma electrolytic oxidation(PEO) has attracted attention as a surface treatment which has high wear resistance and corrosion resistance. PEO is generally considered as cost-effective, environmentally friendly and superior in terms of coating performance. Most of studies about the PEO processes have been applied to light metals such as Al and Mg. Because the strength of Al and Mg is weaker than that of steel, there is a limit to the application. In this study, PEO process was used to form oxide coatings on Hot dipped aluminized(HDA) steel and the characteristics of the coating film according to the PEO current density were studied. The morphology was observed by SEM and component was analyzed by using EDS. The corrosion behaviors of PEO coating films were estimated by exposing salt spray test at 5 wt.% NaCl solution and measuring polarization curves in deaerated 3 wt.% NaCl solution. With the increase of PEO process current density, the pore size of the coating surface and the thickness of coating increased. It was confirmed that no Fe component was present on the coating surface. PEO coating films obviously showed good corrosion resistance compared with HDA. It is considered that the PEO coating acts as a barrier to protect the base material from external factors causing corrosion.

Keywords

Plasma electrolytic oxidation(PEO);Hot-dipped aluminized steel(HDA);Current density;Corrosion resistance;