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Steel 4150 vs 4350

Steel · grade comparison

Steel 4150 and 4350 are both steel grades, both high strength steel. 4350 is the stronger of the two: yield strength 650 MPa (94.3 ksi) against 520 MPa (75.4 ksi) for 4150, about 25% more; tensile strength follows at 1,000 MPa (145 ksi) vs 860 MPa (125 ksi). In exchange, 4150 is the more ductile: elongation 16% versus 12% for 4350, and 4350 is harder (295 HB vs 235 HB). On the shop floor, 4350 sits in a lower cost tier (standard, $$) than 4150 (premium, $$$).

4150Choose it when the part is bent, formed or impact-loaded.

4350Choose it when strength drives the design, or when cost is the deciding factor.

4150 vs 4350: properties

41504350

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

860 MPa125 ksi
1,000 MPa145 ksi

Yield Strength (0.2% offset)

520 MPa75.4 ksi
650 MPa94.3 ksi

Elongation at Break

16%
12%

Reduction in Area

40%
32%

Shear Strength

560 MPa81.2 ksi
640 MPa92.8 ksi

Fatigue Strength (Endurance Limit)

390 MPa56.6 ksi
460 MPa66.7 ksi

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
20 J14.8 ft·lbf

Hardness, Brinell

235 HB
295 HB

Hardness, Rockwell C

21 HRC
31 HRC

Hardness, Vickers

245 HV
—

Fracture Toughness (K_IC)

—
60 MPa·√m54.6 ksi·√in

Same in both: Elastic (Young's) Modulus 205 GPa29.7 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)

1,416°C2,581 °F
1,420°C2,588 °F

Liquidus Temperature

1,490°C2,714 °F
1,480°C2,696 °F

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

42.6 W/m·K24.6 BTU/hr·ft·°F
42 W/m·K24.3 BTU/hr·ft·°F

Specific Heat Capacity

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

Latent Heat of Fusion

250 J/g107 BTU/lb
270 J/g116 BTU/lb

Same in both: Thermal Expansion (CTE, 20–100 °C) 12.3 µm/m·K6.8 µin/in·°F · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

7.8 % IACS
—

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 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)

-0.6 V
—

Same in both: Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

45 / 100
42 / 100

Machinability Rating (AISI 1212 = 100 %)

50%
45%

Weldability

25 / 100
22 / 100

Formability (cold)

25 / 100
22 / 100

Castability

35 / 100
—

Brazeability / Solderability

55 / 100
45 / 100

Polishability

60 / 100
70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

31 MJ/kg13,328 BTU/lb
30 MJ/kg12,898 BTU/lb

Embodied Carbon (primary production)

2.3 kg CO₂/kg
2.2 kg CO₂/kg

Embodied Water

60 L/kg7.2 gal/lb
45 L/kg5.4 gal/lb

Same in both: Typical Recycled Content 30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

110 kN·m/kg
127 kN·m/kg

Modulus of Resilience

660 kJ/m³
1,030 kJ/m³

Thermal Diffusivity

11.5 mm²/s
11.3 mm²/s

Thermal Shock Resistance Index

15
17

Same in both: Specific Stiffness (E / density) 26.1 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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale41504350

Manufacturing and finishing

Capability41504350
Default conditionHRHR
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.

4150 vs 4350 — frequently asked

Is 4350 stronger than 4150?

Yes. 4350 has a typical yield strength of 650 MPa (94.3 ksi) against 520 MPa (75.4 ksi) for 4150 — about 25% more. Tensile strength is 1,000 MPa (145 ksi) vs 860 MPa (125 ksi).

Which is cheaper, 4150 or 4350?

4350 is the lower-cost material: it sits in the standard tier ($$) while 4150 is premium ($$$). 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 4150 over 4350?

Pick 4150 when the part is bent, formed or impact-loaded. Pick 4350 when strength drives the design, or when cost is the deciding factor.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 4150 and 4350 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.