Wires and branches of stainless steel are used for GMAW and GTAW welding, respectively. The products of this group have the same composition and application as stainless-steel electrodes, with the difference that the products of this group have no coating and shielding gas is used to protect against welding.
Welding wires and branches of this category are suitable for welding austenitic steels, heat-resistant austenitic as well as ferritic steels. ER420 welding wire is suitable for welding martensitic stainless steels and ER2209 and ER2594 welding wires are suitable for welding duplex and super duplex stainless steel.
Among the most widely used products in this category, we can mention the ER308 and ER316 families.
– ER308: It has a chemical composition of 16% chromium and 10% nickel. This product is suitable for welding 305, 304, 302, and 301 AISI steel.
– ER308H: It has more carbon than ER308. In addition to increasing strength, carbon addition greatly enhances creep resistance, especially at high temperatures.
– ER308L: Has less carbon than ER308. By reducing carbon, the risk of carbides forming and depositing at the grain boundaries, resulting in the possibility of corrosion between the grains and the resulting cracks, is minimized.
– ER316 has a chemical composition of 18.5% chromium, 12.5% nickel and 2.5% molybdenum. This product is used for welding AISI 316 series stainless steel and similar steels. This product is also used for welding steels that operate at high temperatures. The presence of up to 2.5% molybdenum in the resulting weld metal composition, while increasing the heat resistance, also increases its creep resistance to a significant extent.
– ER316H: It has more carbon than ER316. Due to the fact that more carbon is present in the chemical composition of this product, the tensile strength and creep strength of this product increase, especially at high temperatures.
– ER316L: has less carbon than ER316. For this reason, the risk of grain and interstitial corrosion is minimized. This product is often used for welding low carbon molybdenum austenitic bearing steels. When using the ER316L, keep in mind that this product is less heat resistant than the ER316H.
Introducing Special Products:
- ER309: Products in the 309 families are generally used for welding 309 stainless steels and welding cast and worked heterogeneous steels.
- ER312: This product is generally used for welding 312 cast alloys and for welding heterogeneous metals, especially one of which is high-nickel stainless steel.
- ER385: This product is used for welding 904L steels that serve in corrosive environments containing sulfuric acid or chloride compounds. This product is also used to join 317L alloys as well as welding other stainless steels to 904L steels.
- ER2209: This product was first designed for welding two-phase stainless steels containing 22% chromium. The resulting crystalline structure of the weld is biphasic and consists of ferrite and austenite phases. The weld obtained from this product has high tensile strength and is resistant to corrosion and cracks caused by SCC (stress corrosion).
- ER2594: This product has special alloying elements such as Cr, Mo, Ni, Cu, and N for welding stainless super duplex steels. The presence of these alloying elements has given this product an extraordinary resistance against pitting. The weld metal obtained from ER2594 has an austenitic-ferrite structure which, depending on the heat generated during the welding process and the cooling rate of the molten pool, the percentage of ferrite phase varies from 35 to 65%. The weld obtained from this product, in addition to high resistance against pitting corrosion and stress corrosion, also has high strength and toughness at the same time. This product is widely used in the manufacture of oil and gas equipment, manifolds, pressure pumps, valves and chemical process equipment.