Filler selection for weldments in type 316L stainless steel, for hot organic acid service

• Published in: Corrosion engineering, science, and technology Vol. 46; no. 1; pp. 24 - 31
• Main Authors: Orsmond, C P M, Pistorius, P C
• Format: Journal Article
• Language: English
• Published: London, England Taylor & Francis 01.02.2011; SAGE Publications; Maney; Taylor & Francis Ltd
• Subjects: Applied sciences; Austenitic stainless steel; Austenitic stainless steels; Base metal; Chromium; Corrosion; Corrosion environments; Exact sciences and technology; Exposure; Filler metal; Fillers; Heat resistant steels; Hot organic acid; Joining, thermal cutting: metallurgical aspects; Metals. Metallurgy; Nickel; Organic acids; Solidification; Solidification mode; Stainless steel; Welding; Welds; Austenitic stainless steel; Welds; Solidification mode; Hot organic acid; Welding; Organic acids; Solidification; Welded joint; Corrosion; Austenitic steel; Stainless steel; Microstructure; Stainless steel-316L; Organic compounds
• ISSN: 1478-422X; 1743-2782
• DOI: 10.1179/147842210X12754747500441

The weld metal corrodes much faster than the parent metal if type 316L steel welded with a matching filler is exposed to hot organic acids. Nine commercial filler metals were evaluated by preparing welded coupons and exposing them to different plant environments (with different organic acid mixtures and temperatures) for several months. The filler metals were chosen to yield different solidification modes, and to vary chromium, molybdenum and nickel contents. Only filler metals that are much more highly alloyed than the parent metal gave lower corrosion rates than the parent metal. Partitioning during and after solidification, and the average alloy content, both affect weld bead corrosion.