Steel ER70S-3
EN G2Si1 · JIS YGW11 · GB ER50-3
ER70S-3 is a copper-coated solid mild-steel wire (ER50-3, YGW11, G2Si1) with moderate Mn-Si deoxidizer content for GMAW, GTAW and submerged arc welding.
Reference datasheet — ER70S-3 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the AW condition
ER70S-3 tempers and conditions
ER70S-3 is supplied in 4 conditions, soft to hard. AW is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Stress relieved | For code-mandated PWHT on pressure parts or thick sections: strength drops ~40 MPa, ductility and toughness improve and residual stress/hardness fall. | 400 | 505 | 30 | 145 HB | 10.5 % IACS |
As-welded, submerged arc with neutral flux | Same chemistry supplied as EL12/EM12-class SAW wire; properties depend strongly on flux basicity and heat input, values below are for a neutral agglomerated flux. | 420 | 530 | 28 | 155 HB | 10 % IACS |
As-welded, GTAW/TIG cut lengths under argon | Use 1.6–3.2 mm cut rods with pure Ar for thin sheet, root passes and pipe roots; cleanest, toughest deposit of the three processes. | 430 | 525 | 30 | 150 HB | 10 % IACS |
AWDefault As-welded deposit | Default all-weld-metal condition: 0.8–1.2 mm copper-coated spool wire run with 75–80 % Ar / balance CO₂, spray or short-arc. | 460 | 550 | 28 | 160 HB | — |
Supply forms, finishes and certifications
Ways ER70S-3 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
AW-CO2 | AW-CO₂ | Surface finish |
What is ER70S-3?
ER70S-3 is a copper-coated solid mild-steel wire (ER50-3, YGW11, G2Si1) with moderate Mn-Si deoxidizer content for GMAW, GTAW and submerged arc welding. Typical as-welded deposits give 460 MPa yield, 550 MPa tensile, 28 % elongation and about 160 HB (84 HRB), with less silicon island residue than ER70S-6, which helps on multi-pass joints and parts that will be painted. The lower deoxidation means the base metal must be reasonably clean; on rusty or scaled steel, porosity risk rises and ER70S-6 is the better choice. Deposits have no corrosion resistance. ER70S-3 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,470°C (2,678 °F). ER70S-3 has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 550 MPa (79.8 ksi) — stronger than 55% of steel grades. Elongation at break is 28% and the elastic modulus is 205 GPa (29.7 Msi).
What is ER70S-3 used for?
- general fabrication
- machine building
- TIG filler rod for mild steel
- submerged arc welding
Advantages
- Readily welded — 95/100, better than 97% of steel grades
- Forms and bends easily — 80/100, better than 93% of steel grades
- Ductile — tolerates forming and impact — 28%, better than 89% of steel grades
- High electrical conductivity — 10 % IACS, better than 83% of steel grades
- Conducts heat well — 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades
ER70S-3 properties
Typical room-temperature values for ER70S-3-AW; bars are the position among steel grades.
Physical3
ER70S-3 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,470°C (2,678 °F).
Mechanical16
ER70S-3 has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 550 MPa (79.8 ksi) — stronger than 55% of steel grades. Elongation at break is 28% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
ER70S-3 is rated for continuous service to 400°C (752 °F). It conducts heat at 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
ER70S-3 conducts electricity at 10 % IACS, better than 83% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of ER70S-3 takes about 32 MJ of energy and emits 2.4 kg of CO₂ — more than 70% of steel grades. Typical recycled content is 25%.
Manufacturability8
ER70S-3's machinability is good (58/100, better than 75% of steel grades); weldability excellent (95/100); formability very good (80/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. ER70S-3 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with ER70S-3
Is ER70S-3 easy to machine?
Deposits machine like hot-rolled 1018 (≈60 % of AISI 1212); expect gummy chips, use sharp tools and flood coolant, and dress weld crowns before finish cuts to avoid hard spots in the HAZ.
Can ER70S-3 be welded?
Run DCEP on Ar–CO₂ or CO₂ (GMAW), pure Ar (GTAW) or neutral flux (SAW); base metal must be reasonably free of mill scale, rust and oil because the modest Si content gives limited deoxidation and porosity resistance versus ER70S-6.
Can ER70S-3 be formed, bent or molded?
Supplied as cold-drawn copper-coated spooled wire or straight rods; keep feed-roll pressure and liner condition good since the softer low-Si wire shaves easily and causes birdnesting.
ER70S-3 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 |
|---|---|---|
| CAWS A5.18 ER70S-3 | 0.06 – 0.15 | 0.09 |
| Mn | 0.9 – 1.4 | 1.1 |
| Silower than ER70S-6 (0.80–1.15) | 0.45 – 0.75 | 0.6 |
| P | ≤ 0.03 | 0.01 |
| S | ≤ 0.04 | 0.02 |
| Niresidual | ≤ 0.15 | 0.03 |
| Crresidual | ≤ 0.15 | 0.03 |
| Moresidual | ≤ 0.15 | 0.02 |
| Vresidual | ≤ 0.03 | 0.01 |
| Cuincludes copper coating | ≤ 0.5 | 0.2 |
| Febalance; total other elements ≤0.50 % | balance |
What surface finishes work on ER70S-3?
Deposits rust readily — grind/blast to remove spatter and mill scale, then apply zinc-rich primer, paint, phosphate or galvanizing; not anodizable, and copper coating residue should be cleaned before painting.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel ER70S-3 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- G2Si1
- GB (China)
- ER50-3
- JIS
- YGW11
How much does ER70S-3 cost?
ER70S-3 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
ER70S-3 — frequently asked
What is ER70S-3 used for?
ER70S-3 is typically used for general fabrication, machine building, TIG filler rod for mild steel and submerged arc welding. In short: cleaner deposits than ER70S-6; multi-process MIG/TIG/SAW wire; needs clean base metal.
What is the yield strength of ER70S-3?
ER70S-3 has a typical yield strength of 460 MPa (66.7 ksi) and a tensile strength of 550 MPa (79.8 ksi) — stronger than 55% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is ER70S-3 easy to machine?
Reasonably — machinability is rated good (58/100, better than 75% of steel grades). Deposits machine like hot-rolled 1018 (≈60 % of AISI 1212); expect gummy chips, use sharp tools and flood coolant, and dress weld crowns before finish cuts to avoid hard spots in the HAZ.
Can ER70S-3 be welded?
Yes — weldability is rated excellent (95/100). Run DCEP on Ar–CO₂ or CO₂ (GMAW), pure Ar (GTAW) or neutral flux (SAW); base metal must be reasonably free of mill scale, rust and oil because the modest Si content gives limited deoxidation and porosity resistance versus ER70S-6.
What surface finishes work on ER70S-3?
Deposits rust readily — grind/blast to remove spatter and mill scale, then apply zinc-rich primer, paint, phosphate or galvanizing; not anodizable, and copper coating residue should be cleaned before painting.
Can ER70S-3 be formed, bent or molded?
Supplied as cold-drawn copper-coated spooled wire or straight rods; keep feed-roll pressure and liner condition good since the softer low-Si wire shaves easily and causes birdnesting.
What is the maximum service temperature of ER70S-3?
ER70S-3 is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between ER70S-3-AW and ER70S-3-SR?
AW is the default condition — default all-weld-metal condition: 0.8–1.2 mm copper-coated spool wire run with 75–80 % Ar / balance CO₂, spray or short-arc. SR: for code-mandated PWHT on pressure parts or thick sections: strength drops ~40 MPa, ductility and toughness improve and residual stress/hardness fall. Yield strength is 460 MPa in AW versus 400 MPa in SR.
How much does ER70S-3 cost?
ER70S-3 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- AWS A5.18/A5.18M — Carbon Steel Electrodes and Rods for Gas Shielded Arc Welding — American Welding Society (2021)
- ISO 14341 / EN ISO 14341-A G3Si1-G2Si1 — ISO (2020)
- JIS Z 3312 YGW11 — Japanese Industrial Standards Committee (2009)
- 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)
- Solid wire ER70S-3 all-weld-metal data (Lincoln Electric / Hobart / typical values) — various producers (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.