Steel 18MnMoNi5-5 vs 34MnB5
Steel · grade comparison
Steel 18MnMoNi5-5 and 34MnB5 are both steel grades. 18MnMoNi5-5 is the stronger of the two: yield strength 470 MPa (68.2 ksi) against 420 MPa (60.9 ksi) for 34MnB5, about 12% more. 18MnMoNi5-5 is the more ductile: elongation 22% versus 14% for 34MnB5, and 18MnMoNi5-5 is harder (195 HB vs 185 HB). On the shop floor, 18MnMoNi5-5 welds better (65 vs 55 out of 100).
18MnMoNi5-5Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.
18MnMoNi5-5 vs 34MnB5: 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.
Elastic (Young's) Modulus
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Shear Strength
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Tensile Strength (Ultimate) 620 MPa89.9 ksi · Fatigue Strength (Endurance Limit) 280 MPa40.6 ksi
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.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Min Service Temperature
Same in both: 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 Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Brazeability / Solderability
Same in both: Machinability 55 / 100 · Polishability 55 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Common Calculations
Ratios derived from the values above.
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Same in both: Specific Strength (UTS / density) 79 kN·m/kg · Thermal Shock Resistance Index 10
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 | 18MnMoNi5-5 | 34MnB5 |
|---|---|---|
| Sheet metal | — | Yes |
| Default condition | — | CR |
| Relative cost | $$ Standard | $$ Standard |
| 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.
18MnMoNi5-5 vs 34MnB5 — frequently asked
Is 18MnMoNi5-5 stronger than 34MnB5?
Yes. 18MnMoNi5-5 has a typical yield strength of 470 MPa (68.2 ksi) against 420 MPa (60.9 ksi) for 34MnB5 — about 12% more. Tensile strength is 620 MPa (89.9 ksi) vs 620 MPa (89.9 ksi).
Which is cheaper, 18MnMoNi5-5 or 34MnB5?
Both sit in the same relative cost tier ($$, standard); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which welds better, 18MnMoNi5-5 or 34MnB5?
18MnMoNi5-5. Its weldability rates good (65/100) against good (55/100) for 34MnB5.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 18MnMoNi5-5 and 34MnB5 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.