Laser 용접한 스테인리스강의 용접부위의 부식특성에 관한 평가

• Published in: Han-guk haeyang gonghak hoeji (Online) Vol. 26; no. 4; pp. 64 - 69
• Main Authors: 문경만(Kyung-Man Moon), 원종필(Jong-Pil Won), 박동현(Dong-Hyun Park), 김윤해(Yun-Hae Kim), 이명훈(Myung-Hoon Lee), 김진경(Jin-Gyeong Kim)
• Format: Journal Article
• Language: Korean
• Published: 한국해양공학회 2012
• Subjects: 해양공학; Chromium depletion; Weld metal; 열영향부; 크롬결핍; Corrosion current density; Heat affected zone; 부식전류밀도; 레이저용접; Laser welding; Intergranular corrosion; 입계부식; 용접금속
• ISSN: 1225-0767; 2287-6715

Laser welding was carried out on austenitic 304 (STS 304) and 22 APU stainless steels. In this case, the differences between the corrosion characteristics of the welding zones of the two stainless steels were investigated using electrochemical methods. The Vickers hardness values of the weld metal (WM) zones in both cases, the STS 304 and 22 APU stainless steels, showed relatively higher values than those of other welding zones. The corrosion current densities of the heat affected zone (HAZ) of the 22 APU and the base metal (BM) zone of the STS 304 exhibited the highest values compared to the other welding zones. It is generally accepted that when STS 304 stainless steel is welded using a general welding method, intergranular corrosion is often observed at the grain boundary because of its chromium depletion area. However, when laser welding was performed on both the STS 304 and 22 APU stainless steels, no intergranular corrosion was observed at any of the welding zones. Consequently, it is considered that the intergranular corrosion of stainless steel can be controlled with the application of laser welding.