Alkaline corrosion resistance of slag-free self-shielded titanium-added metal-cored welding overlayAlkalische Korrosionsbeständigkeit von schlackefreien, selbstabschirmenden Metalldraht-Auftragschweißungen mit Titanzusatz

The corrosion resistance of slag-free self-shielded metal-cord welding overlay with different ferrotitanium additions in alkaline solution (pH=14) was investigated. The results show that the self-corrosion potential Ecorr is the highest and the self-corrosion current density Icorr is the minimum when the addition of ferrotitanium is 6 wt. %. titanium carbide corrodes before other carbides in alkaline solution due to the absence of iron. A ferrotitanium addition of 6 wt. % can provide the best corrosion resistance to the fabricated welding overlays, as an increased ferrotitanium addition will result in a decrease in chromium carbide and an increase in titanium carbide, of which titanium carbide is the most prone to corrosion, followed by chromium carbide, and finally the austenitic matrix. The slag-free self-shielded metal-cored welding overlays with different ferrotitanium additions were fabricated. The microstructure and alkaline corrosion behaviour were studied. Finally, the role of titanium on alkaline corrosion resistance was analyzed.image