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Steel ER312 AW-SR

Heat-treated state

UNS S31380

AW-SR = as-welded then stress relieved

Pick when the base metal mandates PWHT; keep hold time short because prolonged exposure embrittles the high-ferrite deposit.

High cost $$$$

Values for the AW-SR condition

Other ER312 tempers and conditions

ER312 is listed in 2 conditions; see the grade overview at ER312.

Compare all 2 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
AW-SRThis page
As-welded then stress relieved
Pick when the base metal mandates PWHT; keep hold time short because prolonged exposure embrittles the high-ferrite deposit.5507502223 HRC2.2 % IACS
AWDefault
As-welded deposit
Standard condition for all-position joining of dissimilar/unknown steels and for buffer layers under hardfacing.5707802524 HRC2.2 % IACS

What is ER312 AW-SR?

ER312 AW-SR is ER312 heat treated to AW-SR — pick when the base metal mandates PWHT; keep hold time short because prolonged exposure embrittles the high-ferrite deposit. ER312 AW-SR has a yield strength of 550 MPa (79.8 ksi) and a tensile strength of 750 MPa (109 ksi) — stronger than 71% of steel grades. Elongation at break is 22% and the elastic modulus is 200 GPa (29 Msi). ER312 AW-SR has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 93% of steel grades. It melts at 1,400°C (2,552 °F). AW is the default condition FabDigit quotes; AW-SR is available on request or by drawing note.

Advantages

  • Good corrosion resistance — 50/100, better than 99% of steel grades
  • Readily welded — 88/100, better than 87% of steel grades

Limitations

  • Poor heat conductor — 16.5 W/m·K (9.53 BTU/hr·ft·°F), worse than 98% of steel grades
  • Low electrical conductivity — 2.2 % IACS, worse than 98% of steel grades
  • High embodied carbon — 4.6 kg CO₂/kg, worse than 96% of steel grades
  • Difficult to machine — 28/100, worse than 91% of steel grades
  • Low fracture toughness — 55 MPa·√m (50.1 ksi·√in), worse than 82% of steel grades

ER312 AW-SR properties

Typical room-temperature values for ER312 AW-SR; 23 are specific to this condition. Other listed values are ER312 reference data and may not represent this condition. Bars are the position among steel grades.

Physical3

ER312 AW-SR has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 93% of steel grades. It melts at 1,400°C (2,552 °F).

Density7.75 g/cm³0.28 lb/in³
Melting Point (Solidus)1,400°C2,552 °F
Liquidus Temperature1,450°C2,642 °F

Mechanical17

ER312 AW-SR has a yield strength of 550 MPa (79.8 ksi) and a tensile strength of 750 MPa (109 ksi) — stronger than 71% of steel grades. Elongation at break is 22% and the elastic modulus is 200 GPa (29 Msi).

Elastic (Young's) Modulus200 GPa29 Msi
Shear Modulus77 GPa11.2 Msi
Bulk Modulus155 GPa22.5 Msi
Poisson's Ratio0.29
Tensile Strength (Ultimate)750 MPa109 ksi
Yield Strength (0.2% offset)550 MPa79.8 ksi
Elongation at Break22%
Reduction in Area32%
Compressive Strength560 MPa81.2 ksi
Shear Strength450 MPa65.3 ksi
Fatigue Strength (Endurance Limit)290 MPa42.1 ksi
Fracture Toughness (K_IC)55 MPa·√m50.1 ksi·√in
Charpy V-Notch Impact (RT)25 J18.4 ft·lbf
Hardness, Brinell245 HB
Hardness, Rockwell B99 HRB
Hardness, Rockwell C23 HRC
Hardness, Vickers258 HV

Thermal6

ER312 AW-SR is rated for continuous service to 315°C (599 °F). It conducts heat at 16.5 W/m·K (9.53 BTU/hr·ft·°F), worse than 98% of steel grades. Thermal expansion is 11.8 µm/m·K (6.56 µin/in·°F).

Thermal Conductivity16.5 W/m·K9.5 BTU/hr·ft·°F
Specific Heat Capacity500 J/kg·K0.12 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)11.8 µm/m·K6.6 µin/in·°F
Latent Heat of Fusion270 J/g116 BTU/lb
Max Service Temperature (continuous)315°C599 °F
Min Service Temperature-30°C-22 °F

Electrical3

ER312 AW-SR conducts electricity at 2.2 % IACS, worse than 98% of steel grades.

Electrical Conductivity2.2 % IACS
Electrical Resistivity7.9×10⁻⁷ Ω·m31.1 µΩ·in
Magnetic Responseferromagnetic

Chemical & Environmental3

Corrosion resistance is fair (50/100), better than 99% of steel grades.

Galvanic Potential (seawater, vs SCE)-0.1 V
Corrosion ResistanceFair50/100
Chemical Resistance SummaryGood atmospheric and mild-oxidising resistance from ~30 % Cr; poor in chlorides and reducing acids, and long exposure above ~315 °C causes sigma-phase embrittlement — not intended as a corrosion-service alloy.

Sustainability4

Producing a kilogram of ER312 AW-SR takes about 55 MJ of energy and emits 4.6 kg of CO₂ — more than 94% of steel grades. Typical recycled content is 55%.

Embodied Energy (primary production)55 MJ/kg23,646 BTU/lb
Embodied Carbon (primary production)4.6 kg CO₂/kg
Embodied Water130 L/kg15.6 gal/lb
Typical Recycled Content55%

Manufacturability7

ER312 AW-SR's machinability is poor (28/100, worse than 91% of steel grades); weldability excellent (88/100); formability poor (32/100).

MachinabilityPoor28/100
Machinability Rating (AISI 1212 = 100 %)32%
WeldabilityExcellent88/100
Formability (cold)Poor32/100
Brazeability / SolderabilityFair50/100
PolishabilityGood55/100
Anodizing Responsen/a — ferrous alloy, not anodised

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with ER312 AW-SR

Is ER312 easy to machine?

Deposits are hard, tough and strongly work-hardening — use rigid setups, sharp carbide, low speed/heavy positive feed, or grind; expect much slower rates than 308L.

Can ER312 be welded?

Very tolerant of dilution and contamination: run low heat input, stringer beads, interpass below ~150 °C, no preheat needed on most steels; limit thickness of high-ferrite deposits in service above ~315 °C.

Can ER312 be formed, bent or molded?

Not a wrought product form — the cold-drawn wire is only bent/coiled for feeding; deposits have limited cold ductility and should not be cold formed.

What surface finishes work on ER312?

Grind or machine buffer layers flat before hardfacing; deposit takes a passive film but polishes/pickles less uniformly than austenitic weld metal due to the two-phase structure.

ER312 chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
C≤ 0.150.1
Cr28 – 3230
Ni8 – 10.59
Mn1 – 2.51.8
Si0.3 – 0.650.45
Moresidual≤ 0.75—
Curesidual≤ 0.75—
P≤ 0.03—
S≤ 0.03—
Febalance—

ER312 AW-SR — frequently asked

What is ER312 AW-SR used for?

ER312 AW-SR is typically used for dissimilar metal welding, cast iron to steel joints, tool steel repair and buffer/buttering layers. In short: most dilution-tolerant stainless filler; standard buffer-layer wire; high-strength duplex deposit.

What is the yield strength of ER312 AW-SR?

ER312 AW-SR has a typical yield strength of 550 MPa (79.8 ksi) and a tensile strength of 750 MPa (109 ksi) — stronger than 71% of steel grades. Strength varies by condition: see the 2 listed tempers.

Is ER312 AW-SR easy to machine?

Not especially — machinability is rated poor (28/100, worse than 91% of steel grades). Deposits are hard, tough and strongly work-hardening — use rigid setups, sharp carbide, low speed/heavy positive feed, or grind; expect much slower rates than 308L.

Can ER312 AW-SR be welded?

Yes — weldability is rated excellent (88/100). Very tolerant of dilution and contamination: run low heat input, stringer beads, interpass below ~150 °C, no preheat needed on most steels; limit thickness of high-ferrite deposits in service above ~315 °C.

What surface finishes work on ER312 AW-SR?

Grind or machine buffer layers flat before hardfacing; deposit takes a passive film but polishes/pickles less uniformly than austenitic weld metal due to the two-phase structure.

Can ER312 AW-SR be formed, bent or molded?

Not a wrought product form — the cold-drawn wire is only bent/coiled for feeding; deposits have limited cold ductility and should not be cold formed.

What is the maximum service temperature of ER312 AW-SR?

ER312 AW-SR is rated for continuous use to about 315°C (599 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between ER312-AW and ER312 AW-SR?

AW is the default condition — standard condition for all-position joining of dissimilar/unknown steels and for buffer layers under hardfacing. AW-SR: pick when the base metal mandates PWHT; keep hold time short because prolonged exposure embrittles the high-ferrite deposit. Yield strength is 570 MPa in AW versus 550 MPa in AW-SR.

Sources

  1. AWS A5.9/A5.9M — Bare Stainless Steel Welding Electrodes and Rods — American Welding Society (2017)
  2. ASM Handbook Vol. 6 — Welding, Brazing and Soldering — ASM International (1993)
  3. ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
  4. ER312 / 312 stainless filler metal weld-metal property sheets — Böhler Welding / Lincoln Electric / ESAB (2023)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.