Welding — filler selection

Pick a welding filler / electrode

The lookup table every WPS engineer keeps in a binder. Type a base metal, see the recommended filler classification, AWS spec, and process notes — same metals AND dissimilar pairs.

55 of 55 pairs

A36 / A516 (CS)A36 / A516 (CS)

preheat: ≥10 °C ambient · 80 °C if t > 25 mm
PWHT: optional below t=38mm
recommended filler
E7018AWS A5.1SMAWlow-H workhorse
ER70S-2 + E7018A5.18 + A5.1GTAW root + SMAW fillhighest quality root
E71T-1A5.20FCAWproductive flux-core
EH14 / Lincolnweld 880A5.17SAWshop fab

A106 (CS pipe)A106 (CS pipe)

preheat: 10 °C ambient (≥80 °C if t>19 mm)
PWHT: optional
recommended filler
E7018AWS A5.1SMAWB31.3 default piping electrode
ER70S-2 + E7018A5.18 + A5.1GTAW root + SMAW filloil-and-gas spec

P11 (1.25Cr-0.5Mo)P11 (1.25Cr-0.5Mo)

preheat: 150 °C
PWHT: mandatory 690 ± 14 °C / 1 h per inch
recommended filler
E8018-B2AWS A5.5SMAWmatching B2 chemistry
ER80S-B2AWS A5.28GTAWtube-mill / repair

P22 (2.25Cr-1Mo)P22 (2.25Cr-1Mo)

preheat: 200 °C
PWHT: mandatory 720 ± 14 °C
recommended filler
E9018-B3AWS A5.5SMAWmatching B3
ER90S-B3AWS A5.28GTAWtube-mill
F9P0-EB3-B3A5.23SAWheader fab

P91 (9Cr-1Mo-V-Nb)P91 (9Cr-1Mo-V-Nb)

preheat: 200-250 °C · interpass <300
PWHT: mandatory 760 ± 10 °C / 4 h min · STRICT
recommended filler
E9015-B91 / E9018-B91AWS A5.5SMAWmatching B91; PWHT critical to develop tempered martensite
ER90S-B91AWS A5.28GTAWmost common root pass
⚠ Warning: P91 PWHT is not optional — under-PWHT yields a brittle as-welded martensite that fails creep test. Hold within ±10 °C and document.

304L (UNS S30403)304L (UNS S30403)

preheat: none (austenitic — pre-heat causes sensitization)
PWHT: NOT permitted (carbide precipitation)
recommended filler
E308L-16AWS A5.4SMAW0.04 % max C, low-C matching filler
ER308LAWS A5.9GTAWhighest quality
ER308LSiAWS A5.9GMAWSi for fluidity

316L (UNS S31603)316L (UNS S31603)

preheat: none
PWHT: NOT permitted
recommended filler
E316L-16AWS A5.4SMAWsour-service spec
ER316LAWS A5.9GTAWmost common piping
ER316LSiAWS A5.9GMAWthicker shop fab

2205 duplex (S31803)2205 duplex (S31803)

preheat: none
PWHT: not required; if applied: 1050-1100 °C solution-anneal
recommended filler
E2209-16AWS A5.4SMAW~22 Cr 9 Ni 3 Mo overmatch Ni for ferrite control
ER2209AWS A5.9GTAWN₂ in shielding gas (1-2 %) recommended
E2209T1-1A5.22FCAWproductive duplex flux-core
⚠ Warning: 2205 needs heat-input control: 0.5-2.5 kJ/mm to keep austenite/ferrite balance. Avoid PWHT — reanneal if exceeded.

2507 super-duplex (S32750)2507 super-duplex (S32750)

preheat: none
PWHT: not required
recommended filler
ER2594AWS A5.9GTAW25Cr-9Ni-4Mo overmatch + 2.4 % Mn
E2594-16AWS A5.4SMAWsour-service piping
⚠ Warning: Heat input 0.5-1.5 kJ/mm strict. N₂ shielding mandatory for GTAW.

316L (austenitic)A106 (carbon steel)

DISSIMILAR
preheat: 50 °C · CS-side rules govern
PWHT: NOT permitted (austenitic side)
recommended filler
ER309L / E309L-16AWS A5.9 / A5.4GTAW + SMAWhigher Cr/Ni overmatch dilutes CS pickup, prevents martensite at fusion line
alternatives
E309LMoAWS A5.4SMAWwhen service requires Mo (CS side at ~150-300 °C)
ENiCrFe-3 (Inconel 182)AWS A5.11GTAWwhen CTE-mismatch fatigue is a concern
⚠ Warning: NEVER use 308L for SS-to-CS — CS dilution drops Cr below 18, martensite forms, joint fails on first thermal cycle.

316L (austenitic)P22 (Cr-Mo)

DISSIMILAR
preheat: 150 °C · P22-side rules govern
PWHT: compromise — partial PWHT below sensitization (450 °C max)
recommended filler
ENiCrFe-3 (Inconel 182) / ERNiCr-3 (Inconel 82)A5.11 / A5.14GTAW + SMAWNi-base buffer — matches CTE between austenitic + ferritic better than 309L
alternatives
ER309L / E309L-16A5.9 / A5.4GTAW + SMAWcheaper but CTE mismatch causes thermal-cycle fatigue at high T

2205 duplexA106 (carbon steel)

DISSIMILAR
preheat: 50 °C
PWHT: not permitted (duplex side anneal-only)
recommended filler
E2209-16 / ER2209A5.4 / A5.9GTAW + SMAWstandard 22-9-3 filler dilutes ~20 % from CS without losing duplex balance
alternatives
ERNiCrMo-3 (Inconel 625)A5.14GTAWwhen fatigue-sensitive or service > 300 °C

Inconel 625 (N06625)Inconel 625 (N06625)

preheat: none
PWHT: not required (precipitation-hardening alloys excepted)
recommended filler
ERNiCrMo-3AWS A5.14GTAWmatching 625 chemistry
ENiCrMo-3AWS A5.11SMAWthicker shop fab

Inconel 625 (N06625)316L stainless

DISSIMILAR
preheat: none
PWHT: NOT permitted
recommended filler
ERNiCrMo-3 / ENiCrMo-3A5.14 / A5.11GTAW + SMAWNi-base side dominates

Hastelloy C-276Hastelloy C-276

preheat: none
PWHT: not required
recommended filler
ERNiCrMo-4AWS A5.14GTAWmatching C-276
ENiCrMo-4AWS A5.11SMAWshop fab

5083 Al-Mg5083 Al-Mg

preheat: none (Al — risk of HAZ over-aging)
PWHT: not applicable
recommended filler
ER5183AWS A5.10GTAW (AC)matching Mg, AC for cleaning
ER5356AWS A5.10GMAW (pulse)most-used for marine 5xxx

CP Ti Gr 2 (R50400)CP Ti Gr 2 (R50400)

preheat: none
PWHT: not required
recommended filler
ERTi-2AWS A5.16GTAW (Ar shield only)matching CP-Ti; full Ar trailing shield mandatory
⚠ Warning: Ti welding: any O₂/N₂ contamination (>500 ppm) = embrittlement. Trailing shield + back-purge mandatory. No air gap allowed.

A572 Gr 50 (HSLA)A572 Gr 50 (HSLA)

preheat: 40 °C above 19 mm · 80 °C above 25 mm
PWHT: often optional
recommended filler
E7018-1AWS A5.1SMAWlow-H workhorse for HSLA
E71T-1CAWS A5.20FCAWproductive for structural

A516 Gr 70 (CS plate)A516 Gr 70 (CS plate)

preheat: 10 °C above 12 mm · 80 °C if t>38 mm
PWHT: mandatory above 38 mm
recommended filler
E7018-A1 if PWHTAWS A5.5SMAWA1 has 0.5Mo for PWHT toughness
ER70S-2 + E7018A5.18 + A5.1GTAW root + SMAW fillpressure-vessel standard
F7A0-EM12K-H4A5.17SAWshop fab

API 5L X65 (line pipe)API 5L X65 (line pipe)

preheat: 10-50 °C
PWHT: not typical for transmission
recommended filler
E8018-G + ER70S-GAWS A5.5 + A5.18GTAW root + SMAW fillmainline X65 girth weld
E7018AWS A5.1SMAWstandard X42-X52

API 5L X70 (line pipe)API 5L X70 (line pipe)

preheat: 50 °C
PWHT: not required
recommended filler
ER80S-G + E8018-GAWS A5.18 + A5.5GTAW root + SMAWmatching strength + low-H

A350 LF2 (low-T forging)A350 LF2 (low-T forging)

preheat: 50 °C · interpass <250
PWHT: mandatory for −46 °C MDMT
recommended filler
ER70S-2 + E7018-A1A5.18 + A5.5GTAW root + SMAW filllow-T impact-tested
⚠ Warning: For LNG / cryogenic service, qualify Charpy at design min temp · NORSOK M-630

A333 Gr 6 (low-T pipe)A333 Gr 6 (low-T pipe)

preheat: 10-100 °C
PWHT: optional unless governed by code
recommended filler
E8018-C3 (1Ni)AWS A5.5GTAW + SMAW1 % Ni filler for −46 °C qual

9% Ni cryogenic9% Ni cryogenic

preheat: none (avoid HAZ overaging)
PWHT: not required
recommended filler
ERNiCrMo-3 (Inconel 625)AWS A5.14GTAWNi-base over-matches strength + cryogenic toughness
ENiCrMo-6AWS A5.11SMAWLNG ship hulls, qualified to −196 °C
⚠ Warning: NEVER use matching 9 % Ni filler - inadequate toughness in HAZ. Use Ni-base.

P5 (5Cr-½Mo)P5 (5Cr-½Mo)

preheat: 200-260 °C
PWHT: mandatory 730 ± 14 °C
recommended filler
E502-15 / E502-16AWS A5.4SMAWmatching 5Cr filler
ER502AWS A5.9GTAWtube fab

P9 (9Cr-1Mo)P9 (9Cr-1Mo)

preheat: 200-260 °C
PWHT: mandatory 730-760 °C
recommended filler
E505-15AWS A5.4SMAWmatching 9Cr (legacy pre-P91)
ER505AWS A5.9GTAWtube

P92 / NF616P92 / NF616

preheat: 200-300 °C · interpass <300
PWHT: mandatory 770 ± 10 °C / 4 h min
recommended filler
E9015-GAWS A5.5SMAWmatching B92 chemistry
ER90S-G (B92 type)AWS A5.28GTAWsupercritical boiler
⚠ Warning: P92 PWHT critical — under-cure same risk as P91

321 (Ti-stab) / 347 (Nb-stab)321 / 347

DISSIMILAR
preheat: none
PWHT: NOT permitted
recommended filler
ER347 (Nb-stab) / ER321 (Ti is rare for filler)AWS A5.9GTAWhigh-T service — Nb stabilizer preferred
E347-16AWS A5.4SMAWrefining hot service

317L / 317LMN317L / 317LMN

preheat: none
PWHT: NOT permitted
recommended filler
ER317LAWS A5.9GTAWhigher Mo for severe pitting
E317L-16AWS A5.4SMAWpulp + paper bleach

904L / N08904904L / N08904

preheat: none
PWHT: NOT permitted
recommended filler
ER385 (904L)AWS A5.9GTAWmatching 904L super-austenitic
E385-16AWS A5.4SMAWsulfuric acid service

254 SMO (S31254)254 SMO (S31254)

preheat: none
PWHT: NOT permitted
recommended filler
ERNiCrMo-3 (alloy 625)AWS A5.14GTAWover-match Ni-base prevents Mo segregation in weld
ENiCrMo-3AWS A5.11SMAWsea water
⚠ Warning: Matching 254-SMO filler segregates Mo. Use Ni-CrMo over-match.

410 / 13Cr martensitic410 / 13Cr martensitic

preheat: 200-260 °C
PWHT: mandatory 700-730 °C if hardness > 22 HRC
recommended filler
E410-16AWS A5.4SMAWmatching martensitic
E309L-16AWS A5.4SMAW (austenitic for ductility)tougher weld but mismatched composition

17-4 PH (S17400)17-4 PH (S17400)

preheat: 50 °C
PWHT: solution + age (per Condition H1025/H1075)
recommended filler
ER630 (matching 17-4)AWS A5.9GTAWmatching PH chemistry
⚠ Warning: PWHT temperature governs final aged strength · solution-anneal then age

Lean duplex 2304Lean duplex 2304

preheat: none
PWHT: not typical · solution anneal if needed
recommended filler
ER2307 / ER2209AWS A5.9GTAWover-match Ni for ferrite balance
E2307-16 / E2209-16AWS A5.4SMAWaustenite-balance critical

ZERON 100 (S32760)ZERON 100 (S32760)

preheat: none
PWHT: not required
recommended filler
ER2594 / Z100XAWS A5.9GTAWmatching W + Cu super-duplex

Inconel 600 (N06600)Inconel 600 (N06600)

preheat: none
PWHT: not required
recommended filler
ERNiCrFe-5 / ERNiCr-3AWS A5.14GTAWmatching 600 for furnace muffles

Inconel 690 (nuclear)Inconel 690 (nuclear)

preheat: none
PWHT: not required
recommended filler
ERNiCrFe-7 (Alloy 152)AWS A5.14GTAWAlloy 52/152 nuclear SG tubes — replaces 600 for SCC resistance

Hastelloy B-3 (N10675)Hastelloy B-3 (N10675)

preheat: none
PWHT: not required
recommended filler
ERNiMo-7AWS A5.14GTAWmatching B-3 for HCl service

Alloy 22 (N06022)Alloy 22 (N06022)

preheat: none
PWHT: not required
recommended filler
ERNiCrMo-10AWS A5.14GTAWmatching Alloy 22
ENiCrMo-10AWS A5.11SMAWsevere oxidising chloride

Alloy 59 (N06059)Alloy 59 (N06059)

preheat: none
PWHT: not required
recommended filler
ERNiCrMo-13AWS A5.14GTAWmatching Alloy 59 ultra-corrosion

Monel 400 (N04400)Monel 400 (N04400)

preheat: none
PWHT: not required
recommended filler
ERNiCu-7 (Alloy 60)AWS A5.14GTAWmatching Monel chemistry
ENiCu-7AWS A5.11SMAWHF acid + sea water

Inconel 800 / 800HInconel 800 / 800H

preheat: none
PWHT: not required
recommended filler
ERNiCr-3 / ERNiCrFe-2AWS A5.14GTAWhigh-T furnace alloy

P22 (Cr-Mo)A106 (CS)

DISSIMILAR
preheat: 200 °C (P22-side dominates)
PWHT: mandatory if P22 thickness > 12 mm
recommended filler
E8018-B2 (P22 chemistry)AWS A5.5SMAWPWHT temperature compatible w/ both sides
ER80S-B2AWS A5.28GTAWmatched to P22

P91 (9Cr)A335 P22 (2¼Cr)

DISSIMILAR
preheat: 200-250 °C · interpass <300
PWHT: mandatory at 740-760 °C (P91 limit)
recommended filler
E9015-B91 (matching P91)AWS A5.5SMAWP91 chemistry dominates because of creep
⚠ Warning: Type IV cracking risk at HAZ — verify Charpy at PWHT temp

P91 (9Cr)A106 (CS)

DISSIMILAR
preheat: 200 °C
PWHT: compromise — often skip on CS-only side
recommended filler
ENiCrFe-3 (Inconel 182)AWS A5.11GTAW + SMAWNi-base buffer better than direct welding for repeated thermal cycling

Inconel 600/625A106 (CS)

DISSIMILAR
preheat: 50-150 °C (CS-side)
PWHT: NOT permitted (Inconel-side)
recommended filler
ENiCrFe-3 / ERNiCr-3A5.11 / A5.14GTAW + SMAWstandard Inconel-CS dissimilar — buffer layer + filler

6061 Al-Mg-Si6061 Al-Mg-Si

preheat: minimal · risk of overaging
PWHT: not applicable
recommended filler
ER4043 (Al-Si)AWS A5.10GTAW (AC)Si-bearing prevents hot cracking
ER5356 (Al-Mg)AWS A5.10GMAWhigher strength than 4043

7075 Al-Zn-Mg-Cu7075 Al-Zn-Mg-Cu

preheat: NOT recommended (HAZ degradation)
PWHT: solution + age required to recover strength
recommended filler
ER5356 (best of bad options)AWS A5.10GTAW (AC)7075 is essentially unweldable for structural use; FSW preferred
⚠ Warning: 7xxx series aluminum is largely unweldable for primary structure · use FSW or mechanical fastening

Ti-6Al-4V (R56400)Ti-6Al-4V (R56400)

preheat: none
PWHT: optional anneal at 540-705 °C
recommended filler
ERTi-5 / ERTi-9AWS A5.16GTAW (Ar)matching 6-4 with O₂ control
⚠ Warning: Same Ti rules: trailing shield + back-purge + clean cavity mandatory

CP Ti Gr 7 (Pd-bearing)CP Ti Gr 7 (Pd-bearing)

preheat: none
PWHT: not required
recommended filler
ERTi-7 (matching Pd)AWS A5.16GTAWpreserve Pd for crevice resistance

Gray cast ironGray cast iron

preheat: 300-540 °C · slow cool
PWHT: slow cool only · stress-relieve at 540 °C
recommended filler
ENiFe-CI (55%Ni / 45%Fe)AWS A5.15SMAW (Ni-base)standard cast-iron repair · machinable
ENi-CIAWS A5.15SMAW (pure Ni)when crack-free is critical, machinable
ESt (steel)AWS A5.15SMAW (graphitic)cheap but not machinable
⚠ Warning: Cast-iron welding risks cracking from rapid cooling. Slow cool below 200 °C in dry insulation.

H13 hot-work tool steelH13 hot-work tool steel

preheat: 370-480 °C · maintain through weld
PWHT: temper after weld
recommended filler
ER80-B2 / matching H13AWS A5.5 / A5.28GTAWdie repair
⚠ Warning: Tool-steel repair welding requires temperature control at every step

90/10 CuNi (C70600)90/10 CuNi (C70600)

preheat: none
PWHT: not required
recommended filler
ERCuNi (alloy 67)AWS A5.7GTAWmatching 90/10 seawater HEX

70/30 CuNi (C71500)70/30 CuNi (C71500)

preheat: none
PWHT: not required
recommended filler
ERCuNi-3 (alloy 67)AWS A5.7GTAWmatching 70/30 seawater

Aluminum bronze (C95400)Aluminum bronze (C95400)

preheat: minimal
PWHT: not typical
recommended filler
ERCuAl-A2AWS A5.7GTAWpump impeller repair
Sources: AWS A5.1 (low-alloy steel SMAW) · A5.4 (SS SMAW) · A5.5 (low-alloy SMAW) · A5.9 (SS bare) · A5.10 (Al) · A5.11 (Ni-base SMAW) · A5.14 (Ni-base bare) · A5.16 (Ti) · A5.17 (CS SAW) · A5.18 (CS bare) · A5.20 (CS FCAW) · A5.22 (SS FCAW) · A5.23 (low-alloy SAW) · A5.28 (low-alloy bare). Always confirm vs the procedure-qualification record (PQR) for the intended service.