Abstract

Micro-arc oxidation (MAO) as an environmentally friendly technology is used to produce ceramic film on metal surfaces to improve its corrosion properties, and the films quality is mainly affected by the electrolyte composition and electrochemical parameters, Here, to improve the corrosion property and wear-resisting of low carbon steel, a compact, corrosion resistant α-Al2O3 ceramic film was prepared on the surface of low carbon steel containing boron (10B21) by MAO. A Na2SiO3 and NaH2PO4 electrolyte system was designed with different content of Na2CO3 and Na2B4O7. The ceramic layer produced with Na2CO3 and Na2B4O7 showed improved corrosion resistance. The corrosion current density was 2.7 μA·cm−2 and the impedance value reached 1900 Ω·cm2. After 7 days of neutral salt spray corrosion, the corrosion rate of this sample coating reduced to 53 g·m−2·h−1. The influence mechanism is discussed. The cooperation of Na2CO3 and Na2B4O7 in the electrolyte is more effectively regulated the ionization and chemical reactions of the MAO process, catalyzing the formation of α-Al2O3. The coating had a uniform thickness of 100 ± 10 μm, no gap between the coating and the substrate was observed, which indicated that the bonding state was good. Thus, the MAO ceramic layer prepared on low carbon steel surface increases the service life of iron and steel components effectively, which can significantly expand its application in more fields.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call