FabDigit

Steel G20Mn5

EN 1.6220

G20Mn5 (EN 1.6220, cross-referenced to ASTM A216 Gr.

Standard cost $$

Reference datasheet — G20Mn5 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 +N condition

G20Mn5 tempers and conditions

G20Mn5 is supplied in 4 conditions, soft to hard. +N is the default FabDigit quotes; the values on this page are for it.

Compare all 4 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Spheroidize annealed
Only for non-critical, low-stress parts or rough blanks that will be heat treated later; coarse dendritic structure gives poor and scattered toughness.28052016160 HB9 % IACS
+NDefault
Normalized
Standard as-supplied condition for structural and general engineering steel castings; balanced strength, toughness and weldability at lowest cost.33056025165 HB—
Normalized and tempered
Pick when residual stresses must be reduced and hardness/toughness scatter tightened on heavy or welded castings without full quenching.34055026160 HB—
Quenched and tempered
Choose for heavier sections or where the highest low-temperature toughness and uniform through-thickness properties are required (wind-turbine and cryogenic-service castings).38058026180 HB—

What is G20Mn5?

G20Mn5 (EN 1.6220, cross-referenced to ASTM A216 Gr. WCC) is a weldable carbon-manganese cast steel supplied normalized, normalized and tempered or quenched and tempered, and is the workhorse grade for structural and general engineering steel castings. It combines 330 MPa yield, 560 MPa tensile, 25 % elongation and 165 HB (85 HRB) with good toughness in sand, shell or investment castings, up to large wind-energy sizes. Weldability is high (score 82, CEV ≈ 0.42–0.48) and machinability 58, but service is limited to about 400 °C and corrosion resistance is that of plain carbon steel. Move to G25NiCrMo3 when higher strength is needed. G20Mn5 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F). G20Mn5 has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 78% of steel grades. Elongation at break is 25% and the elastic modulus is 210 GPa (30.5 Msi).

What is G20Mn5 used for?

  • wind turbine hubs and nacelle castings
  • construction machinery parts
  • railway components
  • general structural steel castings

Advantages

  • Tough — resists crack growth — 120 MPa·√m (109.2 ksi·√in), better than 81% of steel grades
  • Readily welded — 82/100, better than 81% of steel grades
  • Conducts heat well — 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades
  • Ductile — tolerates forming and impact — 25%, better than 77% of steel grades

Limitations

  • Hard to polish — 45/100, worse than 84% of steel grades
  • Limited formability — 20/100, worse than 80% of steel grades
  • Low strength — 330 MPa (47.9 ksi), worse than 78% of steel grades

G20Mn5 properties

Typical room-temperature values for G20Mn5-+N; bars are the position among steel grades.

Physical3

G20Mn5 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).

Density7.85 g/cm³0.28 lb/in³
Melting Point (Solidus)1,425°C2,597 °F
Liquidus Temperature1,510°C2,750 °F

Mechanical16

G20Mn5 has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 78% of steel grades. Elongation at break is 25% and the elastic modulus is 210 GPa (30.5 Msi).

Elastic (Young's) Modulus210 GPa30.5 Msi
Shear Modulus81 GPa11.7 Msi
Bulk Modulus160 GPa23.2 Msi
Poisson's Ratio0.29
Tensile Strength (Ultimate)560 MPa81.2 ksi
Yield Strength (0.2% offset)330 MPa47.9 ksi
Elongation at Break25%
Reduction in Area45%
Compressive Strength330 MPa47.9 ksi
Shear Strength340 MPa49.3 ksi
Fatigue Strength (Endurance Limit)235 MPa34.1 ksi
Fracture Toughness (K_IC)120 MPa·√m109 ksi·√in
Charpy V-Notch Impact (RT)90 J66.4 ft·lbf
Hardness, Brinell165 HB
Hardness, Rockwell B85 HRB
Hardness, Vickers175 HV

Thermal6

G20Mn5 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 12.3 µm/m·K (6.83 µin/in·°F).

Thermal Conductivity48 W/m·K27.7 BTU/hr·ft·°F
Specific Heat Capacity470 J/kg·K0.11 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)12.3 µm/m·K6.8 µin/in·°F
Latent Heat of Fusion270 J/g116 BTU/lb
Max Service Temperature (continuous)400°C752 °F
Min Service Temperature-40°C-40 °F

Electrical3

G20Mn5 conducts electricity at 9 % IACS, better than 71% of steel grades.

Electrical Conductivity9 % IACS
Electrical Resistivity1.9×10⁻⁷ Ω·m7.48 µΩ·in
Magnetic Responseferromagnetic

Chemical & Environmental3

Corrosion resistance is not recommended (11/100), worse than 73% of steel grades.

Galvanic Potential (seawater, vs SCE)-0.62 V
Corrosion ResistanceNot recommended11/100
Chemical Resistance SummaryRusts freely in moist air, seawater and dilute acids; acceptable in dry, oily or alkaline (pH > 10) service and in caustic/neutral water with inhibitors. Requires paint, zinc/epoxy coating or cathodic protection outdoors.

Sustainability4

Producing a kilogram of G20Mn5 takes about 26 MJ of energy and emits 2 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 85%.

Embodied Energy (primary production)26 MJ/kg11,178 BTU/lb
Embodied Carbon (primary production)2 kg CO₂/kg
Embodied Water55 L/kg6.6 gal/lb
Typical Recycled Content85%

Manufacturability8

G20Mn5's machinability is good (58/100, better than 75% of steel grades); weldability very good (82/100); formability poor (20/100).

MachinabilityGood58/100
Machinability Rating (AISI 1212 = 100 %)60%
WeldabilityVery good82/100
Formability (cold)Poor20/100
CastabilityVery good75/100
Brazeability / SolderabilityGood55/100
PolishabilityFair45/100
Anodizing Responsen/a — ferrous alloy; use zinc/nickel plating, phosphating or paint systems instead

Common Calculations5

Specific Strength (UTS / density)calculated71 kN·m/kg
Specific Stiffness (E / density)calculated26.8 MN·m/kg
Modulus of Resiliencecalculated259 kJ/m³
Thermal Diffusivitycalculated13 mm²/s
Thermal Shock Resistance Indexcalculated10

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. G20Mn5 is highlighted; hover a dot for its name, or open the interactive family chart.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scaleG20Mn5

Working with G20Mn5

Is G20Mn5 easy to machine?

Machines like normalized 1020–1030 steel: use coated carbide, 120–200 m/min turning, watch for hard sand/scale skin on the first cut.

Can G20Mn5 be welded?

Excellent weldability (CEV ≈ 0.42–0.48); use low-hydrogen electrodes/wire, preheat 100–150 °C on sections over ~30 mm and PWHT 580–620 °C for critical or heavy repairs.

Can G20Mn5 be formed, bent or molded?

Sand, shell or investment casting with good fluidity but high solidification shrinkage (~2 %); generous risering, chills and directional-solidification design are essential to avoid centerline shrinkage.

G20Mn5 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
C0.17 – 0.230.2
Si≤ 0.60.4
Mn1 – 1.61.3
Pmax 0.025 in some grades of EN 10293≤ 0.020.01
S≤ 0.020.01
Crresidual≤ 0.30.15
Niresidual≤ 0.80.2
Moresidual≤ 0.120.05
Curesidual≤ 0.30.15
Vresidual≤ 0.030.01
Febalance

What surface finishes work on G20Mn5?

No anodizing; shot blast then zinc-rich primer, epoxy paint, hot-dip galvanizing or hard-chrome/nitriding on bearing surfaces for wear.

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).

Equivalent designations

Standards and trade names that resolve to Steel G20Mn5 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.

EN / DIN / Werkstoff-Nr.
1.6220
Similar grades
A216 Gr. WCC

How much does G20Mn5 cost?

G20Mn5 is a standard-cost steel ($$), cheaper than about 71% 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.

G20Mn5 — frequently asked

What is G20Mn5 used for?

G20Mn5 is typically used for wind turbine hubs and nacelle castings, construction machinery parts, railway components and general structural steel castings. In short: workhorse structural cast steel; best-weldable cast steel; wind-energy casting standard.

What is the yield strength of G20Mn5?

G20Mn5 has a typical yield strength of 330 MPa (47.9 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 78% of steel grades. Strength varies by condition: see the 4 listed tempers.

Is G20Mn5 easy to machine?

Reasonably — machinability is rated good (58/100, better than 75% of steel grades). Machines like normalized 1020–1030 steel: use coated carbide, 120–200 m/min turning, watch for hard sand/scale skin on the first cut.

Can G20Mn5 be welded?

Yes — weldability is rated very good (82/100). Excellent weldability (CEV ≈ 0.42–0.48); use low-hydrogen electrodes/wire, preheat 100–150 °C on sections over ~30 mm and PWHT 580–620 °C for critical or heavy repairs.

What surface finishes work on G20Mn5?

No anodizing; shot blast then zinc-rich primer, epoxy paint, hot-dip galvanizing or hard-chrome/nitriding on bearing surfaces for wear.

Can G20Mn5 be formed, bent or molded?

Sand, shell or investment casting with good fluidity but high solidification shrinkage (~2 %); generous risering, chills and directional-solidification design are essential to avoid centerline shrinkage.

What is the maximum service temperature of G20Mn5?

G20Mn5 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 G20Mn5 +N and G20Mn5-AC?

+N is the default condition — standard as-supplied condition for structural and general engineering steel castings; balanced strength, toughness and weldability at lowest cost. AC: only for non-critical, low-stress parts or rough blanks that will be heat treated later; coarse dendritic structure gives poor and scattered toughness. Yield strength is 330 MPa in +N versus 280 MPa in AC.

How much does G20Mn5 cost?

G20Mn5 is a standard-cost steel ($$), cheaper than about 71% 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

  1. EN 10213 — Steel castings for pressure purposes — CEN (2016)
  2. EN 10293 — Steel castings for general engineering uses — CEN (2015)
  3. ASTM A216/A216M Grade WCC — ASTM International (2018)
  4. ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
  5. Steel Castings Handbook — Steel Founders' Society of America / ASM (1995)
  6. SEW 310 — Physical properties of steels — VDEh (1992)

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.