Steel ER70S-6
EN G3Si1 · JIS YGW12 · GB ER50-6
ER70S-6 is a copper-coated solid low-carbon steel welding wire (also designated ER50-6, YGW12, G3Si1) carrying the highest Mn and Si deoxidizer levels in the ER70S family.
Reference datasheet — ER70S-6 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.
ER70S-6 tempers and conditions
ER70S-6 is supplied in one standard condition, PWHT.
Supply forms, finishes and certifications
Ways ER70S-6 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
TIG-ROD | GTAW cut length rod | Supply form |
WIRE-CD | Wire as supplied | Supply form |
AW-C1 | As Welded | Surface finish |
AW-M21Default | As Welded | Surface finish |
What is ER70S-6?
ER70S-6 is a copper-coated solid low-carbon steel welding wire (also designated ER50-6, YGW12, G3Si1) carrying the highest Mn and Si deoxidizer levels in the ER70S family. It is the default GMAW wire for general fabrication because the extra silicon wets rusty or mill-scaled carbon steel, and typical as-welded deposits give 465 MPa yield, 560 MPa tensile, 27 % elongation and about 160 HB (84 HRB); it is stocked as spooled wire and as TIG rod. Deposits have no corrosion resistance and are not matched to Cr-Mo or quenched-and-tempered alloy steels. Use ER70S-3 on clean plate where less silicon residue is wanted. ER70S-6 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-6 has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 560 MPa (81.2 ksi) — stronger than 55% of steel grades. Elongation at break is 27% and the elastic modulus is 205 GPa (29.7 Msi).
What is ER70S-6 used for?
- structural steel welding
- automotive fabrication
- general shop MIG welding
- pipe and tank fabrication
Advantages
- Readily welded — 95/100, better than 97% of steel grades
- High electrical conductivity — 10.5 % IACS, better than 89% of steel grades
- Ductile — tolerates forming and impact — 27%, better than 86% of steel grades
- Conducts heat well — 49 W/m·K (28.3 BTU/hr·ft·°F), better than 83% of steel grades
- Tough — resists crack growth — 120 MPa·√m (109.2 ksi·√in), better than 81% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
ER70S-6 properties
Typical room-temperature values; bars are the position among steel grades.
Physical3
ER70S-6 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-6 has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 560 MPa (81.2 ksi) — stronger than 55% of steel grades. Elongation at break is 27% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
ER70S-6 is rated for continuous service to 400°C (752 °F). It conducts heat at 49 W/m·K (28.3 BTU/hr·ft·°F), better than 83% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
ER70S-6 conducts electricity at 10.5 % IACS, better than 89% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of ER70S-6 takes about 28 MJ of energy and emits 2.1 kg of CO₂ — less than 56% of steel grades. Typical recycled content is 25%.
Manufacturability7
ER70S-6's machinability is good (58/100, better than 75% of steel grades); weldability excellent (95/100); formability good (60/100).
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-6 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with ER70S-6
Is ER70S-6 easy to machine?
Weld deposits machine like 1018/1020 but are gummy and may contain hard spots at fusion lines; use sharp carbide and generous feed.
Can ER70S-6 be welded?
Run 0.8–1.6 mm wire in 100 % CO₂ (short arc/globular) or 75–82 % Ar mix (spray/pulse); high Mn-Si tolerates mill scale and light rust, keep interpass ≤300 °C on structural steel.
Can ER70S-6 be formed, bent or molded?
Supplied as cold-drawn copper-coated spool wire with controlled cast/helix; weldments in this filler bend and cold-form comparably to Q235/A36 base metal.
ER70S-6 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 | 0.06 – 0.15 | 0.08 |
| Mndeoxidizer / strength | 1.4 – 1.85 | 1.55 |
| Sihigh Si for wetting on rusty plate | 0.8 – 1.15 | 0.9 |
| P | ≤ 0.03 | 0.01 |
| S | ≤ 0.04 | 0.02 |
| Ni | ≤ 0.15 | |
| Cr | ≤ 0.15 | |
| Mo | ≤ 0.15 | |
| V | ≤ 0.03 | |
| Cuincludes copper coating | ≤ 0.5 | 0.2 |
| Fe | balance |
What surface finishes work on ER70S-6?
No corrosion resistance of its own — grind flush and paint, zinc-rich prime or hot-dip galvanize; deposits accept plating after proper cleaning.
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-6 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- G3Si1
- GB (China)
- ER50-6
- JIS
- YGW12
- Also called
- AWS ER70S-6
How much does ER70S-6 cost?
ER70S-6 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
ER70S-6 — frequently asked
What is ER70S-6 used for?
ER70S-6 is typically used for structural steel welding, automotive fabrication, general shop MIG welding and pipe and tank fabrication. In short: default mild-steel MIG wire; best tolerance of mill scale; widest availability, lowest cost.
What is the yield strength of ER70S-6?
ER70S-6 has a typical yield strength of 460 MPa (66.7 ksi) and a tensile strength of 560 MPa (81.2 ksi) — stronger than 55% of steel grades.
Is ER70S-6 easy to machine?
Reasonably — machinability is rated good (58/100, better than 75% of steel grades). Weld deposits machine like 1018/1020 but are gummy and may contain hard spots at fusion lines; use sharp carbide and generous feed.
Can ER70S-6 be welded?
Yes — weldability is rated excellent (95/100). Run 0.8–1.6 mm wire in 100 % CO₂ (short arc/globular) or 75–82 % Ar mix (spray/pulse); high Mn-Si tolerates mill scale and light rust, keep interpass ≤300 °C on structural steel.
What surface finishes work on ER70S-6?
No corrosion resistance of its own — grind flush and paint, zinc-rich prime or hot-dip galvanize; deposits accept plating after proper cleaning.
Can ER70S-6 be formed, bent or molded?
Supplied as cold-drawn copper-coated spool wire with controlled cast/helix; weldments in this filler bend and cold-form comparably to Q235/A36 base metal.
What is the maximum service temperature of ER70S-6?
ER70S-6 is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does ER70S-6 cost?
ER70S-6 is a budget-cost steel ($), 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)
- EN ISO 14341 — Wire electrodes for gas shielded metal arc welding (G3Si1/G42 3 M21 3Si1) — ISO (2020)
- Solid GMAW wire ER70S-6 datasheets — Lincoln Electric / ESAB / Kobelco / (2023)
- ASM Handbook Vol.6 Welding, Brazing and Soldering; Vol.1 Properties of Carbon Steels — ASM International (1993)
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.