Steel 4140 vs 52100
Steel · grade comparison
Steel 4140 and 52100 are both steel grades. 4140 is the stronger of the two: yield strength 480 MPa (69.6 ksi) against 415 MPa (60.2 ksi) for 52100, about 16% more. In exchange, 52100 is the more ductile: elongation 25% versus 22% for 4140, and 4140 is harder (210 HB vs 195 HB). 4140 conducts electricity better (7.8 % IACS vs 7 % IACS). On the shop floor, 4140 machines more easily (good vs fair), 4140 welds better (fair vs not recommended), and 4140 sits in a lower cost tier (standard, $$) than 52100 (premium, $$$).
4140Choose it when strength drives the design, or when the part is machined in volume.
52100Choose it when the part is bent, formed or impact-loaded.
4140 vs 52100: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Bulk Modulus
Poisson's Ratio
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Tensile Strength (Ultimate) 690 MPa100 ksi · Shear Strength 420 MPa60.9 ksi
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Max Service Temperature (continuous)
Same in both: Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Same in both: Corrosion Resistance 12 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Brazeability / Solderability
Polishability
Castability
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Same in both: Embodied Carbon (primary production) 2.2 kg CO₂/kg · Embodied Water 55 L/kg6.6 gal/lb · Typical Recycled Content 30%
Common Calculations
Ratios derived from the values above.
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Same in both: Specific Strength (UTS / density) 88 kN·m/kg
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.
Manufacturing and finishing
| Capability | 4140 | 52100 |
|---|---|---|
| Casting & forging | Yes | — |
| Default condition | HR | Annealed |
| Relative cost | $$ Standard | $$$ Premium |
| Min. machined wall | 0.8 mm | 0.8 mm |
| Best machined surface | Ra 1.6 µm | Ra 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.
4140 vs 52100 — frequently asked
Is 4140 stronger than 52100?
Yes. 4140 has a typical yield strength of 480 MPa (69.6 ksi) against 415 MPa (60.2 ksi) for 52100 — about 16% more. Tensile strength is 690 MPa (100 ksi) vs 690 MPa (100 ksi).
Which is cheaper, 4140 or 52100?
4140 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, 4140 or 52100?
4140. Its machinability rates good (60/100) against fair (40/100) for 52100; for welding the order is 4140 first (fair, 40/100) then 52100 (not recommended, 12/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 4140 and 52100 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.