FabDigitFabDigit

Steel 52100 vs SUJ2

Steel · grade comparison

Steel 52100 and SUJ2 are both steel grades, both bearing steel. Both yield at about 415 MPa — strength does not separate them. 52100 runs hotter in service (400°C vs 200°C continuous). On the shop floor, SUJ2 sits in a lower cost tier (standard, $$) than 52100 (premium, $$$).

52100Choose it when the part sees heat.

SUJ2Choose it when cost is the deciding factor.

52100 vs SUJ2: properties

52100SUJ2

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

205 GPa29.7 Msi
210 GPa30.5 Msi

Bulk Modulus

166 GPa24.1 Msi
160 GPa23.2 Msi

Poisson's Ratio

0.3
0.29

Tensile Strength (Ultimate)

690 MPa100 ksi
660 MPa95.7 ksi

Yield Strength (0.2% offset)

415 MPa60.2 ksi
420 MPa60.9 ksi

Compressive Strength

430 MPa62.4 ksi
450 MPa65.3 ksi

Shear Strength

420 MPa60.9 ksi
400 MPa58 ksi

Charpy V-Notch Impact (RT)

15 J11.1 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

195 HB
192 HB

Hardness, Rockwell B

93 HRB
92 HRB

Hardness, Vickers

205 HV
200 HV

Same in both: Shear Modulus 80 GPa11.6 Msi · Elongation at Break 25% · Reduction in Area 45% · Fatigue Strength (Endurance Limit) 320 MPa46.4 ksi

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,424°C2,595 °F
1,425°C2,597 °F

Liquidus Temperature

1,455°C2,651 °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.

Specific Heat Capacity

475 J/kg·K0.11 BTU/lb·°F
460 J/kg·K0.11 BTU/lb·°F

Latent Heat of Fusion

247 J/g106 BTU/lb
250 J/g107 BTU/lb

Max Service Temperature (continuous)

400°C752 °F
200°C392 °F

Same in both: Thermal Conductivity 46 W/m·K26.6 BTU/hr·ft·°F · Thermal Expansion (CTE, 20–100 °C) 11.9 µm/m·K6.6 µin/in·°F · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 7 % IACS · Electrical Resistivity 2.5×10⁻⁷ Ω·m9.84 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.62 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

40 / 100
45 / 100

Castability

25 / 100
30 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 40% · Weldability 12 / 100 · Formability (cold) 35 / 100 · Brazeability / Solderability 35 / 100 · Polishability 85 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

2.2 kg CO₂/kg
2.3 kg CO₂/kg

Same in both: Embodied Energy (primary production) 30 MJ/kg12,898 BTU/lb · Embodied Water 55 L/kg6.6 gal/lb · Typical Recycled Content 30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

88 kN·m/kg
85 kN·m/kg

Specific Stiffness (E / density)

26.2 MN·m/kg
26.9 MN·m/kg

Thermal Diffusivity

12.4 mm²/s
12.8 mm²/s

Thermal Shock Resistance Index

13
12

Same in both: Modulus of Resilience 420 kJ/m³

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 scale52100SUJ2

Manufacturing and finishing

Capability52100SUJ2
Default conditionAnnealedAnnealed
Relative cost$$$ Premium$$ Standard
Min. machined wall0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µm

Both are offered for CNC machining and Sheet metal. Both take the same 38 finishes: AlCrN, AlTiN, Black Oxide, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, Chrome Plating, Copper Plating, CrN, DLC, E-Coating and 26 more.

52100 vs SUJ2 — frequently asked

What is the difference between 52100 and SUJ2?

Steel 52100 and SUJ2 are both steel grades, both bearing steel. Both yield at about 415 MPa — strength does not separate them. 52100 runs hotter in service (400°C vs 200°C continuous).

Which is cheaper, 52100 or SUJ2?

SUJ2 is the lower-cost material: it sits in the standard tier ($$) while 52100 is premium ($$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, 52100 or SUJ2?

SUJ2, by a small margin. Both rate fair for machinability — 45/100 against 40/100 for 52100.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 52100 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.