What is the scope of AWS A5.39 / A5.39M?

AWS A5.39/A5.39M is the American Welding Society specification titled Specification for Flux and Electrode Combinations for Submerged Arc and Electroslag Joining and Surfacing of Stainless Steel and Nickel Alloys.
The standard prescribes classification requirements for flux-electrode combinations used with submerged arc welding (SAW) and electroslag welding (ESW) for joining and surfacing applications.
The base materials covered are stainless steels and nickel alloys.
The specification does not classify welding wire or electrodes as standalone products.
The consumables addressed by this standard are the combined flux-electrode systems, where the electrode classification is referenced from separate AWS filler metal specifications.
Electrode classification is per AWS A5.9/A5.9M for solid and stranded stainless steel electrodes, AWS A5.14/A5.14M for solid and stranded nickel-alloy electrodes, AWS A5.22/A5.22M for cored stainless steel electrodes, and AWS A5.34/A5.34M for cored nickel-alloy electrodes[reference:0][reference:1].
Flux-electrode joining classification is based on the mechanical properties and the composition of weld metal produced with the flux and a specific electrode[reference:2].
Flux-electrode surfacing classification is based on the composition of the weld metal produced with the flux and a specific electrode[reference:3].
The form and usability of the flux are also included as classification criteria.
The current edition is AWS A5.39/A5.39M:2026, which is the second edition and revises the 2020 edition[reference:4].
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[reference:5].

What is the classification system used in AWS A5.39 / A5.39M?

The AWS A5.39 classification system is a composite system that classifies a flux-electrode combination rather than a standalone electrode or flux.
A single classification designation therefore identifies two consumables working together: a specific flux and a specific electrode.
The electrode portion of the classification is not defined within A5.39 itself.
Instead, the electrode is classified according to the requirements of the applicable AWS electrode specification: A5.9/A5.9M for solid and stranded stainless steel electrodes, A5.14/A5.14M for solid and stranded nickel-alloy electrodes, A5.22/A5.22M for cored stainless steel electrodes, and A5.34/A5.34M for cored nickel-alloy electrodes[reference:6].
The flux portion of the classification is designated by a code that begins with the letter “F,” followed by a tensile strength designator, a flux type designator, and, in some cases, additional designators for specific characteristics.
The complete classification designation combines the flux code with the electrode code, separated by a hyphen.
For example, a classification such as F80A15-ER309L/309L identifies a specific flux (F80A15) combined with a specific electrode (ER309L), where the weld metal produced by the combination meets the requirements for the 309L composition[reference:7].
The flux designator itself follows the AWS convention for flux classification: the letter “F” indicates a flux, the two-digit number indicates the minimum tensile strength of the weld metal in thousands of pounds per square inch (or in units of 10 MPa for the M designation), and the letter and number that follow indicate the flux type and usability characteristics.
Verify the complete designator rules and the specific flux type codes with the latest edition.

What is the complete list of AWS A5.39 / A5.39M classifications?

Because AWS A5.39 classifies flux-electrode combinations rather than individual electrodes, the total number of possible classifications is very large and is not fixed in the same way as a standalone electrode specification.
Any qualified flux may be combined with any qualified electrode of the appropriate base metal type to create a classified combination, provided that the combination meets the mechanical property and composition requirements of the standard.
The classification list is therefore not a closed enumeration of electrode types but rather a framework for qualifying and designating combinations.
The electrode types referenced by A5.39 classifications include the full range of classifications covered by A5.9/A5.9M, A5.14/A5.14M, A5.22/A5.22M, and A5.34/A5.34M.
Representative examples of A5.39 classifications drawn from manufacturer data sheets and technical references are listed below.
Because AWS standards are periodically revised and because manufacturer-specific combinations are continually being qualified, verify the complete and current list with the latest edition and with the specific consumable manufacturer.

Stainless steel flux-electrode combination classifications

F80A15-ER309L/309L
F85A15-ER309L/309L
F100A15-ER309LNb/309LNb
F80A15-ER316L/316L
F120A8-ER2594/2594
F80A15-ER308L/308L
These classifications designate flux-electrode combinations for submerged arc welding of stainless steels.
The electrode designations (ER309L, ER316L, ER2594, ER308L) correspond to classifications under AWS A5.9/A5.9M for solid and stranded stainless steel electrodes.
The flux designations (F80A15, F85A15, F100A15, F120A8) identify specific fluxes with designated tensile strength and flux type characteristics.
F80A15 indicates a flux that produces weld metal with a minimum tensile strength of 80,000 psi (or 550 MPa in the M system) and belongs to the A15 flux type category.
F120A8 indicates a higher-strength flux type with a minimum tensile strength of 120,000 psi (or 830 MPa).
ER2594 is a superduplex stainless steel electrode with a composition of approximately 25% Cr, 9% Ni, 4% Mo, and nitrogen, corresponding to UNS S32750.
Verify the complete stainless steel combination list with the latest edition.

Nickel-alloy flux-electrode combination classifications

F100A32-ERNiCrMo-3/NiCrMo-3
F100A32-ERNiCrMo-3/NiCrMo-3
These classifications designate flux-electrode combinations for submerged arc welding of nickel alloys.
The electrode designation ERNiCrMo-3 corresponds to a solid nickel-chromium-molybdenum electrode classified under AWS A5.14/A5.14M, with a composition of approximately 22% Cr, 9% Mo, and 3.5% Nb (Alloy 625 type).
The flux designation F100A32 indicates a flux that produces weld metal with a minimum tensile strength of 100,000 psi (or 690 MPa in the M system) and belongs to the A32 flux type category, which is a high-basic agglomerated flux designed for nickel alloy welding.
The “NiCrMo-3” designation following the electrode code in the classification indicates the weld metal composition produced by the combination.
This combination is used for welding nickel-chromium-molybdenum alloys, dissimilar joints involving nickel alloys and stainless steels, and corrosion-resistant overlays.
Additional nickel-alloy combinations may be qualified with other electrodes from A5.14/A5.14M, such as ERNiCr-3, ERNiCu-7, or ERNiCrMo-4.
Verify the complete nickel-alloy combination list with the latest edition.

Cored electrode flux-electrode combination classifications

Flux-electrode combinations using cored electrodes are classified under A5.39 by referencing electrodes from AWS A5.22/A5.22M (cored stainless steel electrodes) and AWS A5.34/A5.34M (cored nickel-alloy electrodes)[reference:8].
The classification format follows the same structure: flux code followed by a hyphen and the cored electrode code.
For example, a combination using a flux classified as F80A15 with a cored stainless steel electrode such as EC308L would be designated F80A15-EC308L/308L.
The “EC” prefix in the electrode designation indicates a composite (cored) electrode.
The weld metal composition designator (308L in this example) indicates the composition of the weld metal produced by the combination.
Cored electrode combinations offer higher deposition rates and are often used for high-productivity surfacing and joining applications.
Verify the complete cored electrode combination list and the available flux types with the latest edition.

What do the designators in AWS A5.39 / A5.39M classifications signify?

Each element of an AWS A5.39 classification conveys specific technical information about the flux-electrode combination and the weld metal it produces.
The classification designation is structured as FluxDesignator-ElectrodeDesignator/CompositionDesignator.
The flux designator begins with the letter “F,” which indicates a flux.
The two-digit number that follows indicates the minimum tensile strength of the weld metal produced by the combination, expressed in thousands of pounds per square inch for the A5.39 system or in units of 10 MPa for the A5.39M system.
For example, “80” designates a minimum tensile strength of 80,000 psi (550 MPa), and “100” designates 100,000 psi (690 MPa).
The letter and number that follow the strength designator (such as A15, A8, or A32) indicate the flux type, which describes the chemical and physical characteristics of the flux, including its basicity, slag system, and intended application.
The electrode designator follows the hyphen and corresponds to a classification from A5.9/A5.9M, A5.14/A5.14M, A5.22/A5.22M, or A5.34/A5.34M.
The composition designator that follows the slash (/) indicates the nominal composition of the weld metal produced by the combination, which is the basis for the classification of the combination.
For example, in F80A15-ER309L/309L, the “309L” after the slash indicates that the weld metal produced by the F80A15 flux combined with the ER309L electrode meets the composition requirements for 309L stainless steel.
This systematic designation enables welding engineers to select a qualified flux-electrode combination based on the required tensile strength, flux type, electrode composition, and weld metal composition.
Verify the complete designator rules and the specific flux type codes with the latest edition.

What are the mechanical property requirements for A5.39 combinations?

The mechanical property requirements for AWS A5.39 flux-electrode combinations include minimum tensile strength, minimum yield strength, and minimum elongation, along with Charpy V-notch impact toughness where specified.
The tensile strength designator in the flux classification directly correlates to the minimum specified tensile strength of the weld metal produced by the combination.
For a combination classified as F80A15-ER309L/309L, the weld metal must meet a minimum tensile strength of 80,000 psi (550 MPa) as indicated by the “80” designator.
For F100A32-ERNiCrMo-3/NiCrMo-3, the weld metal must meet a minimum tensile strength of 100,000 psi (690 MPa) as indicated by the “100” designator.
The specific yield strength and elongation requirements are determined by the applicable electrode specification and the flux type, and are verified through testing of the actual flux-electrode combination.
Impact toughness requirements, when specified, are verified through Charpy V-notch testing at the designated test temperature.
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 A5.39 combinations?

The chemical composition requirements for AWS A5.39 flux-electrode combinations apply to the weld metal produced by the flux and electrode working together.
The composition designator following the slash in the classification (such as 309L, 316L, 2594, or NiCrMo-3) indicates the nominal composition that the weld metal must meet.
For stainless steel combinations, the composition requirements correspond to the classifications in AWS A5.9/A5.9M for solid and stranded electrodes and AWS A5.22/A5.22M for cored electrodes.
For nickel-alloy combinations, the composition requirements correspond to the classifications in AWS A5.14/A5.14M for solid and stranded electrodes and AWS A5.34/A5.34M for cored electrodes.
The flux can significantly influence the weld metal composition through alloy transfer or elemental loss during welding.
For example, a chromium-compensating flux may add chromium to the weld metal to compensate for chromium loss during the welding process, ensuring that the final weld metal composition meets the 309L or 316L requirements[reference:9].
A flux designed for nickel alloy welding may be formulated to minimize silicon transfer to the weld metal, reducing the risk of hot cracking in nickel-based alloys[reference:10].
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 A5.39/A5.39M.

Which related AWS specifications should be consulted alongside AWS A5.39 / A5.39M?

AWS A5.39/A5.39M does not exist in isolation; several companion specifications provide the electrode classifications that are referenced by the A5.39 system.
AWS A5.9/A5.9M specifies bare stainless steel welding electrodes and rods, and provides the classifications for solid and stranded stainless steel electrodes used in A5.39 combinations[reference:11].
AWS A5.14/A5.14M specifies nickel and nickel-alloy bare welding electrodes and rods, and provides the classifications for solid and stranded nickel-alloy electrodes used in A5.39 combinations[reference:12].
AWS A5.22/A5.22M specifies stainless steel flux cored and metal cored welding electrodes and rods, and provides the classifications for cored stainless steel electrodes used in A5.39 combinations[reference:13].
AWS A5.34/A5.34M specifies nickel-alloy flux cored and metal cored welding electrodes, and provides the classifications for cored nickel-alloy electrodes used in A5.39 combinations[reference:14].
AWS A5.17/A5.17M and AWS A5.23/A5.23M specify carbon steel and low-alloy steel electrodes and fluxes for submerged arc welding, which are the counterparts to A5.39 for non-stainless, non-nickel base materials.
AWS A5.32/A5.32M specifies shielding gases and gas mixtures for fusion welding, which may be relevant for certain electroslag welding applications.
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 stainless steel and nickel-alloy flux-electrode selection, qualification, and quality assurance.

How does AWS A5.39 relate to the broader AWS filler metal classification system?

The AWS filler metal classification system is organized by welding process and product form, with each specification (A5.x) addressing a distinct consumable category.
AWS A5.39 is part of this hierarchical system and addresses flux-electrode combinations for submerged arc and electroslag welding of stainless steels and nickel alloys.
The specification occupies a unique position within the AWS system because it does not classify electrodes or fluxes as standalone products.
Instead, it classifies the combined performance of a specific flux and electrode system, recognizing that the weld metal properties are determined by the interaction between the two consumables.
This approach mirrors the classification philosophy of AWS A5.17/A5.17M and AWS A5.23/A5.23M, which classify flux-electrode combinations for carbon steel and low-alloy steel submerged arc welding, respectively.
The “A5” series covers filler metals and related consumables for arc welding, and the numbering sequence roughly corresponds to the chronological development of the specifications.
The “/A5.39M” 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 was the first edition of the specification, and the 2026 edition represents the second edition, reflecting the ongoing development and refinement of the classification system[reference:15][reference:16].
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 framework with the latest edition of AWS A5.39/A5.39M.