from the conferences organized by TANGER Ltd.
The corrosion resistance of the aluminum-based coating deposited on Inconel Alloy 625 by CVD method was investigated. Specimens of 625 Alloy in as-received state and coated were exposed to static liquid lead at 520 °C. The aim of work was to compare and evaluate the resistance of the coating in different conditions. Two expositions were studied - low oxygen content 10-8 wt.% for 3500 h and cycling of temperature for 1000 h. The results indicate that coatings have good adhesion and could protect the studied alloy from lead corrosion. However, several microscopic anomalies the so-called inner oxidation of alloy under the coating were observed. Corrosion damage was characterized using scanning electron microscopy, which identified the inner oxidation under the coating after exposition. Coating was intact, uniformly applied, without cracks. Local depletion of Cr and Ni was observed within 4.1 μm for low oxygen content and 4.5 μm for cycling exposure and solution-based attack (SBA) was not observed. Specimens without coating were very damaged and destroyed in both exposures because deep penetration of lead was observed.
Keywords: 625 steel, liquid lead, corrosion, coating© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.