Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (34권3호 187-194)

A Study on the Corrosion Behavior by the Moisture on the Surface Layer of the Al-Zn-Si ternary alloys

Al-Zn-Si 3원계 합금도금강판의 부식거동에 관한 연구

김영호;이상래;정원섭;

부산대학교 대학원 금속공학과;부산대학교 금속공학과;

Abstract

Galvalume sheet steel was developed recently, and is used widely in several fields. It has and had a good corrosion resistance in open atmosphere, but it has week corrosion resistance in the ambient surroundings of an airtight packing. Therefore, black patina was synthesized on the surface of Galvalume sheet steel. Corrosion by moisture on a Galvalume surface begins from edge of a droplet and proceeds to the center of droplet. It begins mainly on the interdendritic structure instead of dendritic structure. This suggests that corrosion by moisture occurs on the Zn shrinkage hole from rapid air cooling. In addition, the initial corrosion occurs by the local cell and continues by the oxygen concentration cell.

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