Steel S420MC
EN S420MC
S420MC (Q420M equivalent) is a thermomechanically rolled micro-alloyed hot-rolled sheet steel in the MC cold-forming family, supplied thermomechanically rolled (TM), pickled and oiled, shot blasted or as-welded/stress-relieved, with 460 MPa yield and 540 MPa tensile.
Reference datasheet — S420MC 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 TM condition
S420MC tempers and conditions
S420MC is supplied in 4 conditions, soft to hard. TM 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 |
|---|---|---|---|---|---|---|
As-welded deposit | Design reference for welded S420MC structures — HAZ softening limits joint strength to roughly base-metal minimum. | 410 | 500 | 16 | 190 HB | 9 % IACS |
Stress relieved | Only for dimensional stabilisation of heavily formed/welded assemblies; expect some loss of the TM strength. | 420 | 510 | 25 | 155 HB | 9.5 % IACS |
TMDefault Thermomechanically rolled, as-delivered | Standard mill condition for all S420MC — pick this for laser cutting, roll forming and cold bending of structural sheet. | 460 | 540 | 22 | 165 HB | 9.5 % IACS |
Pickled and oiled thermomechanically rolled strip | Choose when a scale-free, weldable and directly paintable surface is needed for stamped or roll-formed parts. | 460 | 540 | 23 | 163 HB | 9.5 % IACS |
Supply forms, finishes and certifications
Ways S420MC is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
SB | Shot-blasted / descaled plate | Surface finish |
What is S420MC?
S420MC (Q420M equivalent) is a thermomechanically rolled micro-alloyed hot-rolled sheet steel in the MC cold-forming family, supplied thermomechanically rolled (TM), pickled and oiled, shot blasted or as-welded/stress-relieved, with 460 MPa yield and 540 MPa tensile. It is used for load-bearing formed and welded structures where 355 MPa grades are too weak, and comes as coil, sheet and slit strip for laser cutting, punching and roll forming. Elongation is 22 % and formability is lower than S355MC, so bend radii must open up; the steel has no corrosion resistance and must be painted or zinc coated. S460MC is the next strength step. S420MC has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,500°C (2,732 °F). S420MC has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 540 MPa (78.3 ksi) — stronger than 55% of steel grades. Elongation at break is 22% and the elastic modulus is 210 GPa (30.5 Msi).
What is S420MC used for?
- trailer chassis
- agricultural machinery
- crane arms
Advantages
- Forms and bends easily — 78/100, better than 91% of steel grades
- Readily welded — 88/100, better than 87% of steel grades
- High electrical conductivity — 9.5 % IACS, better than 75% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
S420MC properties
Typical room-temperature values for S420MC-TM; bars are the position among steel grades.
Physical3
S420MC has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,500°C (2,732 °F).
Mechanical16
S420MC has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 540 MPa (78.3 ksi) — stronger than 55% of steel grades. Elongation at break is 22% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
S420MC is rated for continuous service to 350°C (662 °F). It conducts heat at 45 W/m·K (26 BTU/hr·ft·°F), better than 66% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
S420MC conducts electricity at 9.5 % IACS, better than 75% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of S420MC takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 25%.
Manufacturability7
S420MC's machinability is good (55/100, better than 62% of steel grades); weldability excellent (88/100); formability very good (78/100).
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. S420MC is highlighted; hover a dot for its name, or open the interactive family chart.
Working with S420MC
Is S420MC easy to machine?
Machinable but tough and stringy — use sharp coated carbide, positive rake and generous feed; most parts are laser/plasma cut and punched rather than machined.
Can S420MC be welded?
Excellent weldability with low CEV; MAG/SAW/laser with matching or slightly under-matched wire, no preheat below ~10 mm, keep heat input moderate to limit HAZ softening.
Can S420MC be formed, bent or molded?
Designed for cold roll forming and press braking — bend transverse to rolling direction, min inner radius ≈ 1 × t; avoid hot forming above ~580 °C which erases TM strength.
S420MC 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 |
|---|---|---|
| CEN 10149-2 max | ≤ 0.12 | 0.08 |
| Si | ≤ 0.5 | 0.2 |
| Mn | ≤ 1.6 | 1.3 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.02 | 0.01 |
| Altotal Al, min | ≥ 0.02 | 0.04 |
| Nbmicro-alloying | ≤ 0.09 | 0.04 |
| Vmicro-alloying | ≤ 0.2 | 0.03 |
| Timicro-alloying | ≤ 0.15 | 0.03 |
| Fe | balance |
What surface finishes work on S420MC?
No inherent corrosion resistance: phosphate + e-coat, powder paint, or hot-dip/electro zinc; pickled-and-oiled surface accepts paint directly after degreasing.
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 S420MC in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Similar grades
- Q420M
How much does S420MC cost?
S420MC 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.
S420MC — frequently asked
What is S420MC used for?
S420MC is typically used for trailer chassis, agricultural machinery and crane arms. In short: mid-range MC strength; roll-forming friendly; trailer chassis standard.
What is the yield strength of S420MC?
S420MC has a typical yield strength of 460 MPa (66.7 ksi) and a tensile strength of 540 MPa (78.3 ksi) — stronger than 55% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is S420MC easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% of steel grades). Machinable but tough and stringy — use sharp coated carbide, positive rake and generous feed; most parts are laser/plasma cut and punched rather than machined.
Can S420MC be welded?
Yes — weldability is rated excellent (88/100). Excellent weldability with low CEV; MAG/SAW/laser with matching or slightly under-matched wire, no preheat below ~10 mm, keep heat input moderate to limit HAZ softening.
What surface finishes work on S420MC?
No inherent corrosion resistance: phosphate + e-coat, powder paint, or hot-dip/electro zinc; pickled-and-oiled surface accepts paint directly after degreasing.
Can S420MC be formed, bent or molded?
Designed for cold roll forming and press braking — bend transverse to rolling direction, min inner radius ≈ 1 × t; avoid hot forming above ~580 °C which erases TM strength.
What is the maximum service temperature of S420MC?
S420MC is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between S420MC-TM and S420MC-AW?
TM is the default condition — standard mill condition for all S420MC — pick this for laser cutting, roll forming and cold bending of structural sheet. AW: design reference for welded S420MC structures — HAZ softening limits joint strength to roughly base-metal minimum. Yield strength is 460 MPa in TM versus 410 MPa in AW.
How much does S420MC cost?
S420MC 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
- EN 10149-2 — Hot-rolled flat products of high yield strength steels for cold forming, thermomechanically rolled — CEN (2013)
- GB/T 1591 — High strength low alloy structural steels (Q420M) — SAC (2018)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.19 — Fatigue and Fracture — ASM International (1996)
- Hot-rolled HSLA strip for cold forming — S420MC datasheet — SSAB / voestalpine / Baosteel (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.