Influence of post-treatment on the corrosion resistance of PEO coated AM50B and AM60B Mg alloys
SURFACE & COATINGS TECHNOLOGY, cilt.205, sa.6, ss.1793-1798, 2010 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 205 Sayı: 6
- Basım Tarihi: 2010
- Doi Numarası: 10.1016/j.surfcoat.2010.08.022
- Dergi Adı: SURFACE & COATINGS TECHNOLOGY
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Sayfa Sayıları: ss.1793-1798
- Anahtar Kelimeler: Plasma Electrolytic Oxidation, Post treatment, Electrochemical corrosion, Magnesium alloys
- Dokuz Eylül Üniversitesi Adresli: Evet
Özet
Magnesium alloys are highly reactive and require protection for their successful applications In this work coatings of 10 mu m and 25 mu m nominal thicknesses were prepared by Plasma Electrolytic Oxidation on AM50B and AM60B alloys The effect of subsequent post-PEO treatments such as alkaline phosphate alkaline silicate and sol-gel sealing was studied on coatings with 10 mu m thickness The microstructure and composition of the PEO coatings and post-treated coatings were analysed by Scanning Electron Microscope and Energy Dispersive X ray Spectroscopy Phase analysis of the coatings was carried out using X-ray Diffraction method Potentiodynamic polarization method was used to evaluate the corrosion behaviour of these coatings in 3 5% NaCl solution Electrochemical corrosion results indicated that the sealed PEO coatings of 10 mu m thickness showed better corrosion resistance than the unsealed PEO coatings of 25 mu m thickness The structural surface defects of the PEO coatings were sealed by post-treatments resulting in decreases in surface roughness and open pores Sol-gel post treatment provided the most effective sealing to the PEO coatings (C) 2010 Elsevier B V All rights reserved