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Steel 100CrMn6 vs SUJ2

Steel · grade comparison

Steel 100CrMn6 and SUJ2 are both steel grades. Both yield at about 410 MPa — strength does not separate them. SUJ2 is the more ductile: elongation 25% versus 22% for 100CrMn6. SUJ2 runs hotter in service (200°C vs 150°C continuous) and SUJ2 conducts electricity better (7 % IACS vs 6 % IACS). On the shop floor, 100CrMn6 sits in a lower cost tier (budget, $) than SUJ2 (standard, $$).

100CrMn6Choose it when cost is the deciding factor.

SUJ2Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

100CrMn6 vs SUJ2: properties

100CrMn6SUJ2

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Poisson's Ratio

0.3
0.29

Yield Strength (0.2% offset)

410 MPa59.5 ksi
420 MPa60.9 ksi

Elongation at Break

22%
25%

Reduction in Area

48%
45%

Compressive Strength

700 MPa102 ksi
450 MPa65.3 ksi

Shear Strength

430 MPa62.4 ksi
400 MPa58 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
—

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

200 HB
192 HB

Hardness, Rockwell B

94 HRB
92 HRB

Hardness, Vickers

210 HV
200 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Tensile Strength (Ultimate) 660 MPa95.7 ksi · Fatigue Strength (Endurance Limit) 320 MPa46.4 ksi

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,400°C2,552 °F
1,425°C2,597 °F

Liquidus Temperature

1,450°C2,642 °F
1,460°C2,660 °F

Same in both: Density 7.81 g/cm³0.28 lb/in³

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

44 W/m·K25.4 BTU/hr·ft·°F
46 W/m·K26.6 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

11.7 µm/m·K6.5 µin/in·°F
11.9 µm/m·K6.6 µin/in·°F

Max Service Temperature (continuous)

150°C302 °F
200°C392 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

6 % IACS
7 % IACS

Electrical Resistivity

3×10⁻⁷ Ω·m11.8 µΩ·in
2.5×10⁻⁷ Ω·m9.84 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.65 V
-0.61 V

Same in both: Corrosion Resistance 12 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability Rating (AISI 1212 = 100 %)

35%
40%

Formability (cold)

40 / 100
35 / 100

Brazeability / Solderability

40 / 100
35 / 100

Castability

—
30 / 100

Same in both: Machinability 45 / 100 · Weldability 12 / 100 · Polishability 85 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

32 MJ/kg13,758 BTU/lb
30 MJ/kg12,898 BTU/lb

Embodied Water

60 L/kg7.2 gal/lb
55 L/kg6.6 gal/lb

Same in both: Embodied Carbon (primary production) 2.3 kg CO₂/kg · Typical Recycled Content 30%

Common Calculations

Ratios derived from the values above.

Modulus of Resilience

400 kJ/m³
420 kJ/m³

Thermal Diffusivity

12.2 mm²/s
12.8 mm²/s

Same in both: Specific Strength (UTS / density) 85 kN·m/kg · Specific Stiffness (E / density) 26.9 MN·m/kg · Thermal Shock Resistance Index 12

Strength versus weight

Yield strength against density for every steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scaleSUJ2100CrMn6

Manufacturing and finishing

Capability100CrMn6SUJ2
CNC machining—Yes
Sheet metal—Yes
Default condition—Annealed
Relative cost$ Budget$$ Standard
Min. machined wall—0.8 mm
Best machined surface—Ra 1.6 µm
AlCrN—Yes
AlTiN—Yes
Black Oxide—Yes
CVD Al2O3—Yes
CVD TiCN—Yes
CVD TiN—Yes
Cerakote—Yes
Chrome Plating—Yes
CrN—Yes
DLC—Yes
E-Coating—Yes
HVOF Coating—Yes
Hot-Dip Galvanizing—Yes
MoS2—Yes
Multilayer CVD—Yes
Nickel Plating—Yes
PTFE Coating—Yes
Painting—Yes

They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

100CrMn6 vs SUJ2 — frequently asked

What is the difference between 100CrMn6 and SUJ2?

Steel 100CrMn6 and SUJ2 are both steel grades. Both yield at about 410 MPa — strength does not separate them. SUJ2 is the more ductile: elongation 25% versus 22% for 100CrMn6.

Which is cheaper, 100CrMn6 or SUJ2?

100CrMn6 is the lower-cost material: it sits in the budget tier ($) while SUJ2 is standard ($$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

When should I choose 100CrMn6 over SUJ2?

Pick 100CrMn6 when cost is the deciding factor. Pick SUJ2 when the part is bent, formed or impact-loaded, or when the part sees heat.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 100CrMn6 and SUJ2 side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.

Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.