자동차용 핫스탬핑 AlSi 도금중 Mg 첨가효과

• Published in: Corrosion science and technology Vol. 20; no. 4; pp. 196 - 203
• Main Authors: 양원석, Wonseog Yang, 이재민, Jeamin Lee, 김창규, Changkyu Kim, 안승호, Seungho Ahn, Homero Castaneda
• Format: Journal Article
• Language: Korean
• Published: 한국부식방식학회 31.08.2021
• Subjects: AlSi coating; Corrosion; Hot stamping; Hydrogen Embrittlement; 금속공학; AlSi coating; Hot stamping; Corrosion; Hydrogen Embrittlement
• ISSN: 1598-6462; 2288-6524
• DOI: 10.14773/cst.2021.20.4.196

To improve corrosion resistance and reduce the hydrogen uptake of 22MnB5, up to 5% Mg was added to the AlSi coating of 22MnB5. After hot-stamping and electrocoating were done on the metallic-coated specimen, the surface characteristics of the steel, hydrogen uptake content, and corrosion resistance were examined by transmittance electron microscopy, thermal desorption spectrometry, cyclic corrosion testing, and electrochemical impedance spectroscopy. Mg was investigated as MgO on the surface layer after hotstamping while it existed as Mg 2 Si before hot-stamping. The total hydrogen content of 22MnB5 was decreased along with the Mg content. However, there was no difference at 0.2 wt% or more. When a small amount of Mg was added, the coating corrosion resistance was decreased, but when it was added at around 1.0 wt%, the greatest corrosion resistance increase was seen. However, when 3 wt% or more was added excessively, the corrosion resistance was decreased. MgO on the surface was considered to suppress H uptake by the AlSi melting solution and increase the barrier effect of the coating.