Metal dusting behaviour of welded Ni-base alloys with different surface finish

• Published in: Materials and corrosion Vol. 54; no. 10; pp. 785 - 792
• Main Authors: Grabke, H. J., Müller-Lorenz, E. M., Zinke, M.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Weinheim WILEY-VCH Verlag 01.10.2003; WILEY‐VCH Verlag; Wiley-VCH
• Subjects: Applied sciences; Corrosion; Corrosion mechanisms; Exact sciences and technology; heat affected zone; Joining, thermal cutting: metallurgical aspects; metal dusting; Metals. Metallurgy; Ni-base alloys; Ni-Basis-Legierungen; Oberflächenzustand; surface finish; TIG- and hand-weldments; TIG- und Handschweißungen; Welding; Wärmeeinflusszone; Nickel base alloys; Corrosion mechanism; Welding; Dusting; Experimental study; Corrosion product; Weld; Welding metallurgy; Corrosion; Desintegration; Corrosion test; Microstructure; Surface conditions
• ISSN: 0947-5117; 1521-4176
• DOI: 10.1002/maco.200303734

Welded Ni‐base alloys and Alloy 800 were exposed under metal dusting conditions at 600°C and 650°C for up to 6000 hours. Alloy 800 was attacked very strongly already in the first days and Alloy 600 also rather soon and widespread, on both materials attack started mainly in the heat affected zone. Several surface states of Alloy 600: brushed, ground, sand‐blasted and pickled were tried only grinding caused a modest delay and decrease of metal dusting attack. Generally the attack was less widespread but deeper at 650°C than at 600°C, also for Alloy 601 and 602. The latter alloys show minor, mainly local attack, but especially the welds are affected. TIG welding led to better resistance than hand‐welding.