What is the scope of AWS A5.34 / A5.34M?
AWS A5.34/A5.34M is the American Welding Society specification that prescribes classification requirements for nickel-alloy flux cored and metal cored welding electrodes.
The standard covers tubular electrodes for flux cored arc welding (FCAW) as well as metal cored electrodes that may be used with various welding processes.
The specification includes compositions in which the nickel content exceeds that of any other element.
Nickel-base alloy compositions intended for the joining of cast irons are explicitly excluded from this standard.
For flux cored electrodes, classification is based on the chemical composition, mechanical properties, soundness of the weld metal, and welding position usability characteristics of the electrode using the specified shielding gas.
For metal cored electrodes, testing determines the chemical composition using the chemical compositions specified in AWS A5.14/A5.14M.
The current edition is AWS A5.34/A5.34M:2026, which supersedes the 2020 edition.
The specification uses both U.S. Customary Units and the International System of Units (SI), and each system must be used independently of the other.
Verify the current edition number and any superseded designations with the latest edition.
What is the classification system used in AWS A5.34 / A5.34M?
The AWS A5.34 classification system uses the prefix “E” to denote an electrode, followed by the chemical symbol “Ni” to indicate a nickel-base alloy.
The alloying elements that follow the “Ni” designation identify the primary alloy system: Cr for chromium, Mo for molybdenum, Fe for iron, Cu for copper, and Co for cobalt.
A numeral following the alloying element designation specifies the particular composition range within that alloy family.
The letter “T” followed by a numeral (T0 or T1) indicates the electrode type and usability characteristics: T0 designates a flux cored electrode with flat and horizontal position capability, while T1 designates an all-position flux cored electrode.
The numeral following the hyphen denotes the shielding gas condition: “-1” designates 100% CO₂, “-4” designates a CO₂ and argon mixture (typically 75–80% Ar with balance CO₂), and other numerals designate alternative gas mixtures.
Some classifications may include a “Z” designator to indicate a composition that is a modification of a standard classification.
The AWS A5.34M designations follow the same structure but use ISO 12153-compatible format designations (e.g., TNi 6625-14 for ENiCrMo3T1-4).
Verify the complete designator rules with the latest edition.
What is the complete list of AWS A5.34 / A5.34M classifications?
The classifications below are compiled from publicly available manufacturer data sheets, technical reference tables, and product catalogs.
The AWS A5.34/A5.34M standard contains a finite number of classified electrode types, and not every composition family necessarily has a corresponding classification.
Because AWS standards are periodically revised, verify the complete and current list with the latest edition.
Nickel-chromium-molybdenum (ENiCrMo) classifications
ENiCrMo3T1-4
ENiCrMo3T0-4
ENiCrMo4T1-1/-4
ENiCrMo4T0-4
ENiCrMo10T1-1/-4
ENiCrCoMo1T0-4
ENiMo13T1-4
These classifications designate nickel-chromium-molybdenum electrodes for welding nickel-base alloys such as Alloy 625, Alloy C-276, and Alloy 825, as well as superaustenitic stainless steels and 9% Ni steels for cryogenic applications.
ENiCrMo3T1-4 corresponds to the NiCr22Mo9Nb composition (Alloy 625) and is one of the most widely used classifications in the A5.34 system.
ENiCrMo4T1-1/-4 corresponds to the NiCr15Mo16Fe6W4 composition (Alloy C-276) for highly corrosive environments.
ENiCrMo10T1-1/-4 is designed for welding nickel-chromium-molybdenum alloys with high molybdenum content for severe corrosion resistance.
ENiMo13T1-4 is a nickel-molybdenum classification for applications requiring resistance to hydrochloric acid and other reducing environments.
Verify the complete ENiCrMo list with the latest edition.
Nickel-chromium-iron (ENiCrFe) classifications
ENiCrFe1T1-4
ENiCrFe2T1-4
ENiCrFe2T0-1
ENiCrFe3T1-1/-4
ENiCrFe3T0-4
These classifications designate nickel-chromium-iron electrodes for welding high-nickel alloys such as Inconel 600, Incoloy 800, and dissimilar joints between stainless steel, low-alloy steel, and nickel-base alloys.
ENiCrFe1T1-4 is a general-purpose classification for dissimilar welding and clad steel applications.
ENiCrFe2T1-4 offers improved crack resistance compared to ENiCrFe1 and is suitable for a broader range of dissimilar joints.
ENiCrFe3T1-1/-4 and ENiCrFe3T0-4 correspond to the NiCr15Fe6Mn composition (Alloy 182 type) and are widely used for buffer layers, cladding on 5% and 9% Ni steels, and repair of difficult-to-weld steels.
The “T0” version (ENiCrFe3T0-4) is limited to flat and horizontal positions, while the “T1” version (ENiCrFe3T1-1/-4) is suitable for all positions.
Verify the complete ENiCrFe list with the latest edition.
Nickel-chromium (ENiCr) and nickel-copper (ENiCu) classifications
ENiCr3T1-4
ENiCr3T0-4
ENiCu7T0-4
ENiCr3T1-4 and ENiCr3T0-4 correspond to the NiCr20Mn3Nb composition (Alloy 82 type) and are used for welding nickel-chromium alloys, dissimilar joints, and for cladding applications.
The “T1” version is suitable for all positions, while the “T0” version is limited to flat and horizontal positions.
ENiCu7T0-4 corresponds to the NiCu30Mn3Ti composition (Alloy 400 type) with increased titanium to suppress porosity.
It is used for cladding and weld overlay on steel, for welding nickel-copper alloys such as Alloy 400 and Alloy K500, and for heterogeneous welds between nickel-copper alloys and steels.
Verify the complete ENiCr and ENiCu lists with the latest edition.
Additional specialty classifications
ENiCrCoMo1T0-4
ENiMo13T1-4
ENiCrCoMo1T0-4 is a nickel-chromium-cobalt-molybdenum classification for high-temperature applications requiring creep resistance and corrosion resistance.
ENiMo13T1-4 is a nickel-molybdenum classification for severe reducing acid environments.
Additional specialty classifications may exist within the A5.34 system, including variations with different shielding gas designators or position capabilities.
For a definitive enumeration of every classification, consult the latest edition of AWS A5.34/A5.34M.
What do the shielding gas designators and position designators signify?
The shielding gas designator in the classification suffix specifies the composition of the shielding gas required for the electrode.
The numeral “1” designates 100% CO₂ shielding.
The numeral “4” designates a mixture of CO₂ and argon, typically 75–80% argon with the balance CO₂ (classified as M21 under ISO 14175).
The letter “Z” preceding a classification number, as in the A5.34M designations, indicates a composition that is a modification of the standard classification or a composition for which the requirements are established by agreement.
The position designator in the “T” portion of the classification specifies the welding positions for which the electrode is suitable.
“T0” designates a flux cored electrode suitable for flat and horizontal positions only, typically with a rutile-basic slag system.
“T1” designates a flux cored electrode suitable for all positions, including vertical and overhead, with a fast-freezing slag system.
These designators enable welding engineers to select the appropriate electrode for the joint position and the available shielding gas supply.
Verify the specific shielding gas ranges and position capabilities for each classification with the latest edition.
What are the mechanical property requirements for AWS A5.34 electrodes?
The mechanical property requirements for AWS A5.34 nickel-alloy flux cored electrodes include minimum tensile strength, minimum yield strength, minimum elongation, and Charpy V-notch impact toughness at specified test temperatures.
For ENiCrMo3T1-4 (NiCr22Mo9Nb composition), typical minimum values include a tensile strength of 690 MPa (100 ksi), a yield strength of 400 MPa (58 ksi), and an elongation of 25%, with impact toughness of 70 J at –196°C for cryogenic applications.
For ENiCrFe3T1-1/-4 (NiCr15Fe6Mn composition), typical values include a tensile strength of 550 MPa (80 ksi), a yield strength of 360 MPa (52 ksi), and an elongation of 25%, with impact toughness of 70 J at –196°C.
For ENiCu7T0-4 (NiCu30Mn3Ti composition), typical minimum values include a tensile strength of 480 MPa (70 ksi), a yield strength of 200 MPa (29 ksi), and an elongation of 27%, with impact toughness of 47 J at +20°C.
The precise mechanical property tables are contained within the standard and should be consulted directly for design and qualification purposes.
Verify all mechanical property requirements with the latest edition.
What are the chemical composition requirements for AWS A5.34 electrodes?
For flux cored electrodes classified under AWS A5.34, the chemical composition requirements apply to the weld metal produced by the electrode.
ENiCrMo3T1-4 (NiCr22Mo9Nb) specifies chromium at 20.0–23.0%, molybdenum at 8.0–10.0%, niobium plus tantalum at 3.15–4.15%, iron at ≤5.0%, and nickel as the balance.
ENiCrFe3T1-1/-4 (NiCr15Fe6Mn) specifies chromium at 13.0–17.0%, iron at 6.0–10.0%, manganese at 5.0–9.5%, niobium plus tantalum at 1.0–2.5%, and nickel at ≥59.0%.
ENiCu7T0-4 (NiCu30Mn3Ti) specifies nickel at 62.0–68.0%, copper at 28.0–34.0%, manganese at 2.0–4.0%, titanium at 1.5–2.5%, and iron at ≤2.5%.
For classifications with the “Z” designator, the chemical composition may be a modification of a standard classification and is typically established by agreement between supplier and purchaser.
The precise chemical composition tables are contained within the standard and should be consulted directly for design and qualification purposes.
Verify all compositional requirements with the latest edition of AWS A5.34/A5.34M.
AWS A5.34/A5.34M does not exist in isolation; several companion specifications provide complementary coverage for nickel and nickel-alloy filler metals across different welding processes and product forms.
AWS A5.14/A5.14M specifies nickel and nickel-alloy bare welding electrodes and rods for gas shielded arc welding; the metal cored electrodes classified under A5.34 use the chemical compositions specified in A5.14/A5.14M.
AWS A5.11/A5.11M specifies nickel and nickel-alloy welding electrodes for shielded metal arc welding (SMAW), covering compositions such as ENiCrFe-2, ENiCrFe-3, ENiCrMo-3, and ENiCu-7 in covered electrode form.
AWS A5.22/A5.22M specifies stainless steel flux cored and metal cored welding electrodes and rods, which share similar tubular electrode construction and classification logic with A5.34 but address stainless steel compositions.
AWS A5.9/A5.9M specifies bare stainless steel welding electrodes and rods, which are relevant for dissimilar joints involving stainless steel and nickel alloys.
The ASME Boiler and Pressure Vessel Code, Section II, Part C, adopts AWS filler metal specifications as SFA specifications; users should confirm the corresponding SFA edition for their application.
Consulting these specifications together provides a comprehensive framework for nickel-alloy filler metal selection, qualification, and quality assurance.
The AWS filler metal classification system is organized by welding process and base metal type, with each specification (A5.x) addressing a distinct process or product form.
AWS A5.34 is part of this hierarchical system and addresses nickel-alloy flux cored and metal cored electrodes specifically.
The “A5” series covers filler metals for arc welding, and the numbering sequence roughly corresponds to the chronological development of the specifications.
The “/A5.34M” suffix indicates that the specification includes both U.S. Customary Units and SI units, a convention applied to AWS standards that have been harmonized with ISO practices.
The 2020 edition introduced the classification of metal cored electrodes, expanding the scope of the specification beyond flux cored electrodes alone.
Users should always confirm that they are working from the most current edition of any AWS specification, as classifications and requirements may be added, revised, or withdrawn between editions.
Verify the current edition number and the complete classification list with the latest edition of AWS A5.34/A5.34M.
