The filler wire for super duplex stainless steel usually needs to be selected according to the specific welding requirements and application scenarios.
The following are some common filler wires for super duplex stainless steel
1. ERNiCrMo-3, ERNiCrMo-4 and ER309L
A study used pulsed current gas tungsten arc welding (PCGTAW) technology to connect 5 mm thick super duplex steel (UNS S32750) and austenitic stainless steel (AISI 304) using three filler wires: ERNiCrMo-3, ERNiCrMo-4 and ER309L.
The mechanical properties of the welded joints were evaluated by impact, tensile and microhardness tests, and the microstructural changes were studied using optical microscopy. The results showed that the yield strength to ultimate tensile strength ratio and ultimate tensile strength of the welded joints using ERNiCrMo-4 filler wire were higher, 0.6 and 642MPa, respectively. At the same time, the microhardness of the welded joints of this filler wire was also higher than that of the other two filler wires. Impact test results show that the ERNiCrMo-4 filler wire welded joint exhibits superior toughness of 189J.
2. ER2594
In wire arc additive manufacturing technology, ER2594 filler wire is used to manufacture thin walls. Microstructural examination shows the presence of ferrite, intragranular austenite, widmanstattenite, grain boundary austenite, and secondary austenite. Due to the complex cyclic thermal history during deposition, the austenite-ferrite ratio varies throughout the wall. Due to the low heat input and suitable interpass temperature, no harmful phases such as sigma phase or lambda phase are observed. Microhardness measurements show a gradual change in hardness along the build direction (281–310HV₀.₂). The tensile specimens exhibit anisotropy and have better tensile properties than their forged counterparts, meeting the minimum requirements mentioned in ASTM A240/A240M-20a and ANSI/NACE MR0175/ISO 15156-1:2015.
3. E2209T0-1
For 2205 duplex steel, the weldability was analyzed and flux-cored arc welding was selected for welding, and E2209T0-1 welding wire was selected as the filler metal. The test results show that the 2205 duplex stainless steel welded joints welded with E2209T0-1 welding wire as the filler metal meet the standard requirements.
