Rutile-coated MMA electrode for welding super duplex alloys for service in the as-welded condition. This electrode is overmatching with respect to nickel content to achieve the correct austenite-ferrite microstructural phase balance. Recovery is about 105% with respect to the core wire, and 65% with respect to the whole electrode.
Applications
Super duplex stainless steel pipe, plate, fittings and forgings have an approximate 50:50 microstructure of austenite with a ferrite matrix. This, coupled with the general alloying level, confers:
- High strength compared with standard austenitic steels, e.g. type 316L
- Good general corrosion resistance in a range of environments
- High resistance to chloride-induced stress corrosion cracking (CSCC)
- High resistance to pitting attack in chloride environments, e.g. seawater. These alloys are finding widening application in the offshore oil/gas, chemical and petrochemical process industries, e.g. pipework systems, flowlines, risers, manifolds etc.
Specification
AWS A5.4: E2594-16
BS EN 1600: E 25 9 4 N L R 3 2