Mechanical and micro-examination characterization of welded joints in UNS S32760 for offshore applications

The Duplex stainless steels are materials that possess excellent mechanical characteristics with good corrosion resistance, even more, compared to conventional stainless steels. In the oil and gas industry, this fact benefits since the components design, with smaller thicknesses (and therefore lighter), did not compromised the corrosion resistance and avoids expensive anti-corrosion coatings. For welding, Super Duplex steels must be managed on a par with austenitic but with precautions, to limit the joints sensitization to corrosion caused by welding with too mild thermal cycles i (range 1000 to 600 degrees C). This paper describes the setting up and verification of welded joints in a steel type UNS S32760 (Super Duplex F55) for use in an offshore environment. The joint was created using the two manual welding processes TIG (GTAW) and coated electrode (SMAW), to obtain the mechanical and micro-examination characteristics desired for the project.