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Steel 4027 vs 4150

Steel · grade comparison

Steel 4027 and 4150 are both steel grades. 4150 is the stronger of the two: yield strength 520 MPa (75.4 ksi) against 330 MPa (47.9 ksi) for 4027, about 58% more; tensile strength follows at 860 MPa (125 ksi) vs 500 MPa (72.5 ksi). In exchange, 4027 is the more ductile: elongation 30% versus 16% for 4150, and 4150 is harder (235 HB vs 143 HB). On the shop floor, 4027 machines more easily (good vs fair), 4027 welds better (good vs poor), and 4027 sits in a lower cost tier (budget, $) than 4150 (premium, $$$).

4027Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

4150Choose it when strength drives the design.

4027 vs 4150: properties

40274150

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

500 MPa72.5 ksi
860 MPa125 ksi

Yield Strength (0.2% offset)

330 MPa47.9 ksi
520 MPa75.4 ksi

Elongation at Break

30%
16%

Reduction in Area

62%
40%

Compressive Strength

330 MPa47.9 ksi
—

Shear Strength

330 MPa47.9 ksi
560 MPa81.2 ksi

Fatigue Strength (Endurance Limit)

245 MPa35.5 ksi
390 MPa56.6 ksi

Fracture Toughness (K_IC)

90 MPa·√m81.9 ksi·√in
—

Charpy V-Notch Impact (RT)

55 J40.6 ft·lbf
25 J18.4 ft·lbf

Hardness, Brinell

143 HB
235 HB

Hardness, Rockwell B

78 HRB
—

Hardness, Vickers

150 HV
245 HV

Hardness, Rockwell C

—
21 HRC

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)

1,420°C2,588 °F
1,416°C2,581 °F

Liquidus Temperature

1,500°C2,732 °F
1,490°C2,714 °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

44 W/m·K25.4 BTU/hr·ft·°F
42.6 W/m·K24.6 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

12.2 µm/m·K6.8 µin/in·°F
12.3 µm/m·K6.8 µin/in·°F

Min Service Temperature

-30°C-22 °F
-40°C-40 °F

Same in both: Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 400°C752 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

7.5 % IACS
7.8 % IACS

Electrical Resistivity

2.3×10⁻⁷ Ω·m9.06 µΩ·in
2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.61 V
-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

60 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
50%

Weldability

60 / 100
25 / 100

Formability (cold)

60 / 100
25 / 100

Castability

40 / 100
35 / 100

Brazeability / Solderability

70 / 100
55 / 100

Same in both: Polishability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

25 MJ/kg10,748 BTU/lb
31 MJ/kg13,328 BTU/lb

Embodied Carbon (primary production)

1.9 kg CO₂/kg
2.3 kg CO₂/kg

Embodied Water

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

Same in both: Typical Recycled Content 30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

64 kN·m/kg
110 kN·m/kg

Modulus of Resilience

266 kJ/m³
660 kJ/m³

Thermal Diffusivity

11.9 mm²/s
11.5 mm²/s

Thermal Shock Resistance Index

9
15

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 scale41504027

Manufacturing and finishing

Capability40274150
CNC machining—Yes
Sheet metal—Yes
Default condition—HR
Relative cost$ Budget$$$ Premium
Min. machined wall—0.8 mm
Best machined surface—Ra 1.6 µm
AlCrN—Yes
AlTiN—Yes
Black Oxide—Yes
CVD Al2O3—Yes
CVD TiCN—Yes
CVD TiN—Yes
Cerakote—Yes
Chrome Plating—Yes
CrN—Yes
DLC—Yes
E-Coating—Yes
HVOF Coating—Yes
Hot-Dip Galvanizing—Yes
MoS2—Yes
Multilayer CVD—Yes
Nickel Plating—Yes
PTFE Coating—Yes
Painting—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.

4027 vs 4150 — frequently asked

Is 4150 stronger than 4027?

Yes. 4150 has a typical yield strength of 520 MPa (75.4 ksi) against 330 MPa (47.9 ksi) for 4027 — about 58% more. Tensile strength is 860 MPa (125 ksi) vs 500 MPa (72.5 ksi).

Which is cheaper, 4027 or 4150?

4027 is the lower-cost material: it sits in the budget 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.

Which is easier to machine, 4027 or 4150?

4027. Its machinability rates good (60/100) against fair (45/100) for 4150; for welding the order is 4027 first (good, 60/100) then 4150 (poor, 25/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 4027 and 4150 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.