Basic coated all-positional MMA electrode for welding superduplex 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. It is designed for the most demanding vertical and overhead welding positions such as fixed pipework qualified in the ASME 5G/6G position, and for applications requiring the highest toughness. Recovery is about 105% with respect to the core wire, 65% with respect to the whole electrode.
Applications
Superduplex 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 eg. 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 eg. seawater. These alloys are finding widening application in the offshore oil/gas, chemical and petrochemical process industries, eg. pipework systems, flowlines, risers, manifolds etc
Specification
AWS A5.4: E2954-15
BS EN 1600: E 25 9 4 N L B 4 2