CHARACTERISTICS & APPLICATIONS
íshín-2594R deposits weld metal containing 25.5 Cr, 10 Ni, 4 Mo, and 0.25 N. The sum of the Cr + 3.3 (Mo + 0.5 W) + 16 N, known as the Pitting Resistance Equivalent Number (PREN), is at least 40, thereby allowing the weld metal to be called a “super-duplex stainless steel.” This number is a semi-quantitative indicator of resistance to pitting in aqueous chloride-containing environments. It is designed for the welding of Type 2507 super duplex stainless steels UNS S32750 (wrought) and UNS J93404 (cast), and similar compositions. It can also be used for the welding of carbon and low-alloy steels to duplex stainless steels as well as to weld “standard” duplex stainless steels such as Type 2205 although the weld metal impact toughness may be inferior to that from E2209 electrodes. If post weld annealing is required, this weld metal will require a higher annealing temperature than that required by the duplex base metal.
The covering for these electrodes generally contains readily ionizing elements to stabilize the arc for welding with alternating current. Electrode sizes 4.0 mm and smaller may be used in all positions of welding.
Storage and Drying Conditions: Hydrogen can have adverse effects on welds in some steels under certain conditions. One source of this hydrogen is moisture in the electrode coverings. For this reason, the proper storage, treatment, and handling of electrodes are necessary.
Holding Ovens: 125°C–150°C.
Drying Conditions: 250°C–425°C for 1 hour prior to use.
CHEMICAL COMPOSITION OF UNDILUTED WELD
| C | Cr | Ni | Mo | Nb+Ta | Mn | Si | P | S | N | Cu | Others |
| 0.04 | 24.0-27.0 | 8.50-10.50 | 3.50-4.50 | NS | 0.50-2.00 | 1.00 | 0.04 | 0.03 | 0.20-0.3.00 | 0.75 | NS |
Single values are maxima, except where specified otherwise.
ALL-WELD-METAL MECHANICAL PROPERTIES
| Tensile Strength, MPa | Yield Strength, At
0.2% Offset, MPa |
Elongation % | Lateral Expansion,
mm |
Charpy V-Notch
Impact at NS°C, Joules |
| 760 | NS | 15 | NS | NS |
Single values are minimal.
ELECTRODE SIZE & WELDING CURRENT (AC and DCEP)
| DIAMETER, mm | LENGTH, mm | Amperes |
| 2.50 | 350 | 65-90 |
| 3.15, 3.20 | 350 | 90-120 |
| 4.00 | 350 | 120-150 |
| 5.00 | 350 | 160-200 |
WARNING: Safety and health information is available from many sources, including, but not limited to Safety and Health Fact Sheets listed in A11.3, ANSI Z49.1 Safety in Welding, Cutting, and Allied Processes published by the American Welding Society, 8669 Doral Blvd., Suite 130, Doral, FL 33166., and applicable federal and state regulations. The Safety and Health Fact Sheets are revised, and additional sheets added periodically.