Can you use SMAW with E7018 on A514?

No. A514 has a minimum yield strength of 100 ksi. E7018 is a 70 ksi class electrode — substantially undermatched. AWS A5.5 low-hydrogen electrodes in the E10018, E11018, or E12018 class are required to achieve the tensile properties the WPS qualification test demands. Undermatch may be acceptable in certain design scenarios only when the engineer explicitly approves it and the PQR documents the resulting weld properties.

What is the maximum interpass temperature for A514 welding?

AWS D1.1 limits maximum interpass temperature for A514 to 400°F [205°C] to protect the quenched-and-tempered microstructure. Exceeding this threshold softens the heat-affected zone and can reduce tensile properties below the required minimum. Document this limit explicitly on the WPS and measure it in production.

Does A514 require PWHT under AWS D1.1?

Generally no — postweld heat treatment is not required and is actively harmful for A514. Typical stress-relief temperatures (1100–1200°F range) destroy the quenched-and-tempered temper and reduce base metal mechanical properties significantly. Your WPS should explicitly prohibit PWHT unless a full requalification has been performed with the heat treatment applied during the PQR test.

Can A514 use a prequalified WPS under AWS D1.1?

No. A514 is not on the AWS D1.1 prequalified base metal list. Any WPS for A514 must be supported by a PQR with complete mechanical testing — tensile, bend, and CVN if required. The qualification test plates should use the actual heat of material or a verified equivalent matching the CE of production material.

WPS requirements for A514 high-strength steel welding

A514 quenched and tempered steel requires preheat, low-hydrogen process, and heat input limits. What your WPS must document under AWS D1.1:2025.

ASTM A514 quenched-and-tempered (QT) structural steel appears in heavy crane girders, pressure vessel supports, mining equipment structures, and high-restraint splice connections where lighter steel would require impractically thick sections. Its 100 ksi minimum yield strength makes it attractive for load-critical details, but QT microstructure is far more sensitive to welding heat than A36 or A572. A WPS that works on mild structural steel will not work on A514 — and using it anyway risks HAZ softening, hydrogen cracking, or weld metal that can't meet tensile requirements.

This article covers the WPS content requirements and production controls that AWS D1.1:2025 and sound QC practice demand for A514.

What makes A514 different

A514 achieves its strength through a heat-treatment cycle — austenitizing, quenching, and tempering. This QT condition produces a fine-grained martensitic microstructure with high strength and reasonable toughness. The tempered condition is temperature-sensitive: if the base metal in the HAZ or the weld metal is held above the original tempering temperature for any meaningful time, the temper is relieved and strength drops.

This creates constraints on welding that don't apply to normalized or hot-rolled steels:

Heat input must be limited to prevent excessive HAZ width and temperature
Preheat must be high enough to prevent hydrogen cracking but not so high that it pushes base metal above the tempering temperature for extended periods
Interpass temperature has a hard upper ceiling
PWHT at conventional stress-relief temperatures is destructive, not remedial

Standard WPS documentation approaches that work for A36 or A572 — sometimes using a prequalified procedure with minimal documentation of heat input — are inadequate for A514.

A514 is not a prequalified base metal

AWS D1.1's prequalified WPS path (Clause 4) specifies a list of base metals eligible for prequalification. A514 is not on it. There is no shortcut here: every WPS for A514 must be backed by a PQR with:

Full tensile testing of weld metal and the weld-HAZ interface
Bend testing per D1.1 requirements
CVN impact testing if the contract or structural code requires it

The PQR test plates should use material from the same heat, or a heat with a similar carbon equivalent, as the production material. A514 comes in multiple grades (A, B, E, F, H, and others); the alloy composition varies by grade. A PQR qualified on A514 Grade B does not automatically cover Grade F if the CE values differ significantly.

For the mechanics of PQR tensile and bend testing, see PQR tensile and bend test requirements.

Preheat requirements

Because A514 is not prequalified, there is no single AWS D1.1 prequalified preheat table value to cite. Minimum preheat is established through one of two routes:

PQR-qualified preheat: The minimum preheat applied during the PQR test defines the minimum permitted in production. Using a lower preheat than the PQR is an essential variable violation under Table 6.6.
Carbon equivalent calculation: AWS D1.1 Annex I provides a CE-based methodology for estimating minimum preheat. For most A514 grades, CE values typically fall in the 0.50–0.75 range, which translates to elevated preheat requirements — commonly 150–225°F [65–107°C] for sections under 1-1/2 in [38 mm] and up to 300°F [150°C] for heavier sections. Verify actual values using the CE method on the material certification you have in hand.

Whatever preheat your WPS specifies, document it explicitly with minimum and maximum values. "Preheat as required" is not a conforming WPS entry.

Rule library based on AWS D1.1:2025; verify against your governing edition.

Maximum interpass temperature

The maximum interpass temperature for A514 welding is 400°F [205°C]. This limit is not arbitrary — it is tied to the tempering temperature of the QT condition. Running above 400°F during multipass welding means each subsequent pass is soaking adjacent base metal and previously deposited weld metal at a temperature approaching the temper range.

In heavy-plate multipass welds, maintaining interpass temperature is operationally difficult. Welders working on thick sections with high preheat often find interpass temperature climbing with each pass. Your QC procedure must include:

Interpass measurement before striking each pass
A cooling protocol when interpass approaches the limit (typically enforced with a temperature-indicating crayon or contact thermometer)
Documentation of measured interpass temperatures in the inspection record

This is not optional process paperwork — it directly affects whether the base metal properties declared on the material certification are still valid in the finished joint.

Filler metal selection

A514 requires matching or overmatching tensile strength. AWS A5.5 low-hydrogen electrodes in the following classes are typically used:

E10018-D2 or E10018-M: 100 ksi minimum tensile, hydrogen designation H8 or H4 required
E11018-M: 110 ksi minimum tensile, used where the joint design requires overmatching
E12018-M: 120 ksi minimum tensile, for specific high-strength joint requirements

For GMAW and FCAW-G on A514, select AWS A5.28 or A5.29 classifications with appropriate strength levels. The WPS must document the complete classification, including the hydrogen designator (-H4, -H8) if low-hydrogen compliance is required.

E7018 — the standard low-hydrogen electrode for A36/A572 work — is undermatched for A514. Even if the joint is designed for the weld metal yield strength to fall below base metal yield (intentional undermatch for ductility management), that design decision must appear in the structural engineer's specification and the WPS must document it explicitly, not happen by accident.

See low-hydrogen electrode storage and SMAW WPS for hydrogen control procedures — the same practices apply to the higher-strength classifications used on A514, except the strength class shifts up significantly.

Heat input limits

Heat input must be limited on A514 for two reasons: preventing excessive HAZ width (which softens base metal in the tempered-zone) and controlling cooling rate (which affects weld metal toughness).

Your WPS must document:

Minimum and maximum amperage for each electrode size
Minimum and maximum voltage range
Minimum travel speed (sets the upper heat input bound)
Maximum travel speed (sets the lower heat input bound, which affects interpass preheat requirements)

The calculated heat input range from those parameters should be validated during PQR testing. Any production weld that falls outside the heat-input range qualified by the PQR is an essential variable violation. See heat input control and documentation for how to calculate and log heat input during production.

PWHT: do not apply to A514

This deserves emphasis because it is counterintuitive. PWHT is frequently specified as a "fix" for residual stress in welded structures. On A514, standard stress-relief PWHT temperatures (1100–1200°F [595–650°C]) exceed the original tempering temperature. The result is a progressive reduction in base metal tensile strength in the heated zone — potentially dropping 100 ksi yield material below 80 ksi in the heat-affected area.

If an engineer has a legitimate reason to apply PWHT to an A514 joint — for example, in a vessel application where code requires stress relief — the procedure must be qualified by test with PWHT applied during the PQR, and the mechanical test results must demonstrate that strength requirements are still met after heat treatment. This is a project-specific engineering decision, not a routine WPS option.

A514 WPS documentation checklist

Before deploying an A514 WPS in production:

PQR on file, same or equivalent base metal grade
WPS lists A514 base metal specification and grade
Minimum preheat stated in °F and °C; method of measurement specified
Maximum interpass temperature 400°F [205°C] explicitly listed
Filler metal lists full AWS classification including hydrogen designator
Amperage, voltage, and travel speed ranges documented (heat input derivable)
Maximum single-pass size stated (especially for SMAW)
PWHT: "Not permitted" or specific qualified PWHT procedure referenced
CVN test results in PQR if seismic or fracture-critical application

For the framework on how essential variable changes in the WPS tie back to PQR qualification ranges, see WPS essential variables vs. nonessential variables.

A514 WPS qualification is not the place to discover documentation gaps. See how WPS software handles high-strength steel procedure management.