Environmental Degradation of Dissimilar Austenitic 316L and Duplex 2205 Stainless Steels Welded Joints

Archives of Metallurgy and Materials

Łabanowski J.¹  Topolska S.² 

[1] Department of Materials and Welding Engineering, Gdańsk University of Technology, 11/12G. Narutowicza Str., 80-233Gdańsk, Poland;Institute of Engineering Materials and Biomaterials, Silesian University of Technology, 18A Konarskiego Str., 44-100Gliwice, Poland;

关键词: duplex steel 2205;    austenitic steel 316L;    welded joints;    stress corrosion cracking (SCC);    hydrogen embrittlement;   

DOI  :  10.1515/amm-2017-0312

来源: DOAJ

【 摘 要 】

The paper describes structure and properties of dissimilar stainless steels welded joints between duplex 2205 and austenitic 316L steels. Investigations were focused on environmentally assisted cracking of welded joints. The susceptibility to stress corrosion cracking (SCC) and hydrogen embrittlement was determined in slow strain rate tests (SSRT) with the strain rate of 2.2 × 10−6 s−1. Chloride-inducted SCC was determined in the 35% boiling water solution of MgCl2 environment at 125°C. Hydrogen assisted SCC tests were performed in synthetic sea water under cathodic polarization condition. It was shown that place of the lowest resistance to chloride stress corrosion cracking is heat affected zone at duplex steel side of dissimilar joins. That phenomenon was connected with undesirable structure of HAZ comprising of large fractions of ferrite grains with acicular austenite phase. Hydrogen assisted SCC tests showed significant reduction in ductility of duplex 2205 steel while austenitic 316L steel remains almost immune to degradation processes. SSR tests of dissimilar welded joints revealed a fracture in the area of austenitic steel.

【 授权许可】

Unknown