Steel ER312-AW (As-welded deposit)
Heat-treated state · default condition
UNS S31380
Standard condition for all-position joining of dissimilar/unknown steels and for buffer layers under hardfacing.
Values for the AW condition
Other ER312 tempers and conditions
ER312 is listed in 2 conditions; see the grade overview at ER312.
- AW-SR
- AW
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As-welded then stress relieved | Pick when the base metal mandates PWHT; keep hold time short because prolonged exposure embrittles the high-ferrite deposit. | 550 | 750 | 22 | 23 HRC | 2.2 % IACS |
AWDefaultThis page As-welded deposit | Standard condition for all-position joining of dissimilar/unknown steels and for buffer layers under hardfacing. | 570 | 780 | 25 | 24 HRC | 2.2 % IACS |
What is ER312-AW?
ER312-AW is ER312 heat treated to AW — standard condition for all-position joining of dissimilar/unknown steels and for buffer layers under hardfacing. ER312-AW has a yield strength of 570 MPa (82.7 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 74% of steel grades. Elongation at break is 25% and the elastic modulus is 200 GPa (29 Msi). ER312-AW 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).
Advantages
- Good corrosion resistance — 55/100, better than 99% of steel grades
- Readily welded — 90/100, better than 90% of steel grades
- Ductile — tolerates forming and impact — 25%, better than 77% of steel grades
Limitations
- Poor heat conductor — 16 W/m·K (9.24 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 — 25/100, worse than 93% of steel grades
ER312-AW properties
Typical room-temperature values for ER312-AW; 24 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 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).
Mechanical17
ER312-AW has a yield strength of 570 MPa (82.7 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 74% of steel grades. Elongation at break is 25% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
ER312-AW is rated for continuous service to 315°C (599 °F). It conducts heat at 16 W/m·K (9.24 BTU/hr·ft·°F), worse than 98% of steel grades. Thermal expansion is 11.8 µm/m·K (6.56 µin/in·°F).
Electrical3
ER312-AW conducts electricity at 2.2 % IACS, worse than 98% of steel grades.
Chemical & Environmental3
Corrosion resistance is good (55/100), better than 99% of steel grades.
Sustainability4
Producing a kilogram of ER312-AW takes about 55 MJ of energy and emits 4.6 kg of CO₂ — more than 94% of steel grades. Typical recycled content is 55%.
Manufacturability7
ER312-AW's machinability is poor (25/100, worse than 93% of steel grades); weldability excellent (90/100); formability poor (30/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ER312-AW
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.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| C | ≤ 0.15 | 0.1 |
| Cr | 28 – 32 | 30 |
| Ni | 8 – 10.5 | 9 |
| Mn | 1 – 2.5 | 1.8 |
| Si | 0.3 – 0.65 | 0.45 |
| Moresidual | ≤ 0.75 | — |
| Curesidual | ≤ 0.75 | — |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
ER312-AW — frequently asked
What is ER312-AW used for?
ER312-AW 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?
ER312-AW has a typical yield strength of 570 MPa (82.7 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 74% of steel grades. Strength varies by condition: see the 2 listed tempers.
Is ER312-AW easy to machine?
Not especially — machinability is rated poor (25/100, worse than 93% 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 be welded?
Yes — weldability is rated excellent (90/100). 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?
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 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?
ER312-AW 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
- AWS A5.9/A5.9M — Bare Stainless Steel Welding Electrodes and Rods — American Welding Society (2017)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering — ASM International (1993)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- 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.