Steel 34MnB5 vs 37Cr4
Steel · grade comparison
Steel 34MnB5 and 37Cr4 are both steel grades. 37Cr4 is the stronger of the two: yield strength 520 MPa (75.4 ksi) against 420 MPa (60.9 ksi) for 34MnB5, about 24% more; tensile strength follows at 780 MPa (113 ksi) vs 620 MPa (89.9 ksi). 37Cr4 is the more ductile: elongation 17% versus 14% for 34MnB5, and 37Cr4 is harder (235 HB vs 185 HB). On the shop floor, 34MnB5 welds better (good vs fair) and 37Cr4 sits in a lower cost tier (budget, $) than 34MnB5 (standard, $$).
34MnB5Choose it when it will be welded.
37Cr4Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.
34MnB5 vs 37Cr4: 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.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Compressive Strength
Hardness, Rockwell C
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29
Physical
Density and transition temperatures.
Melting Point (Solidus)
Liquidus Temperature
Same in both: Density 7.85 g/cm³0.28 lb/in³
Thermal
How each material carries heat and how hot it can run.
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Min Service Temperature
Same in both: Thermal Conductivity 44 W/m·K25.4 BTU/hr·ft·°F · Max Service Temperature (continuous) 400°C752 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Same in both: Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
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)
Embodied Water
Same in both: Embodied Carbon (primary production) 2 kg CO₂/kg · Typical Recycled Content 25%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Same in both: Specific Stiffness (E / density) 26.8 MN·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 | 34MnB5 | 37Cr4 |
|---|---|---|
| Sheet metal | Yes | — |
| Default condition | CR | — |
| Relative cost | $$ Standard | $ Budget |
| Min. machined wall | — | — |
| Best machined surface | — | — |
| Black Oxide | Yes | — |
| Cerakote | Yes | — |
| Chrome Plating | Yes | — |
| E-Coating | Yes | — |
| Hot-Dip Galvanizing | Yes | — |
| Nickel Plating | Yes | — |
| PTFE Coating | Yes | — |
| Painting | Yes | — |
| Powder Coating | Yes | — |
| Tin Plating | Yes | — |
| Zinc Plating | Yes | — |
| Zinc-Flake (Dip-Spin) Coating | Yes | — |
| Zinc-Nickel Plating | 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.
34MnB5 vs 37Cr4 — frequently asked
Is 37Cr4 stronger than 34MnB5?
Yes. 37Cr4 has a typical yield strength of 520 MPa (75.4 ksi) against 420 MPa (60.9 ksi) for 34MnB5 — about 24% more. Tensile strength is 780 MPa (113 ksi) vs 620 MPa (89.9 ksi).
Which is cheaper, 34MnB5 or 37Cr4?
37Cr4 is the lower-cost material: it sits in the budget tier ($) while 34MnB5 is standard ($$). 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, 34MnB5 or 37Cr4?
34MnB5. Its machinability rates good (55/100) against fair (50/100) for 37Cr4; for welding the order is 34MnB5 first (good, 55/100) then 37Cr4 (fair, 35/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 34MnB5 and 37Cr4 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.