FabDigit

9255 vs 4140 and 2 more: properties

9255414041505160

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Shear Modulus

79 GPa11.5 Msi
80 GPa11.6 Msi
80 GPa11.6 Msi
80 GPa11.6 Msi

Tensile Strength (Ultimate)

1,760 MPa255 ksi
690 MPa100 ksi
860 MPa125 ksi
725 MPa105 ksi

Yield Strength (0.2% offset)

1,620 MPa235 ksi
480 MPa69.6 ksi
520 MPa75.4 ksi
275 MPa39.9 ksi

Elongation at Break

8%
22%
16%
17%

Reduction in Area

25%
50%
40%
31%

Compressive Strength

1,650 MPa239 ksi
480 MPa69.6 ksi

Shear Strength

1,060 MPa154 ksi
420 MPa60.9 ksi
560 MPa81.2 ksi
450 MPa65.3 ksi

Fatigue Strength (Endurance Limit)

720 MPa104 ksi
345 MPa50 ksi
390 MPa56.6 ksi
330 MPa47.9 ksi

Fracture Toughness (K_IC)

40 MPa·√m36.4 ksi·√in
110 MPa·√m100 ksi·√in

Charpy V-Notch Impact (RT)

14 J10.3 ft·lbf
40 J29.5 ft·lbf
25 J18.4 ft·lbf
25 J18.4 ft·lbf

Hardness, Brinell

495 HB
210 HB
235 HB
197 HB

Hardness, Rockwell C

50 HRC
21 HRC

Hardness, Vickers

520 HV
220 HV
245 HV

Hardness, Rockwell B

94 HRB
92 HRB

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Density

7.8 g/cm³0.28 lb/in³
7.85 g/cm³0.28 lb/in³
7.85 g/cm³0.28 lb/in³
7.85 g/cm³0.28 lb/in³

Melting Point (Solidus)

1,400°C2,552 °F
1,416°C2,581 °F
1,416°C2,581 °F
1,425°C2,597 °F

Liquidus Temperature

1,470°C2,678 °F
1,483°C2,701 °F
1,490°C2,714 °F
1,490°C2,714 °F

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
42.6 W/m·K24.6 BTU/hr·ft·°F
46 W/m·K26.6 BTU/hr·ft·°F

Specific Heat Capacity

475 J/kg·K0.11 BTU/lb·°F
473 J/kg·K0.11 BTU/lb·°F
473 J/kg·K0.11 BTU/lb·°F
490 J/kg·K0.12 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

11.8 µm/m·K6.6 µin/in·°F
12.3 µm/m·K6.8 µin/in·°F
12.3 µm/m·K6.8 µin/in·°F
12.3 µm/m·K6.8 µin/in·°F

Max Service Temperature (continuous)

250°C482 °F
425°C797 °F
400°C752 °F
250°C482 °F

Same in both: Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

5.7 % IACS
7.8 % IACS
7.8 % IACS
7.8 % IACS

Electrical Resistivity

3×10⁻⁷ Ω·m11.8 µΩ·in
2.2×10⁻⁷ Ω·m8.66 µΩ·in
2.2×10⁻⁷ Ω·m8.66 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)

-0.6 V
-0.61 V
-0.6 V
-0.61 V

Corrosion Resistance

11 / 100
12 / 100
12 / 100
10 / 100

Manufacturability

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

Machinability

25 / 100
60 / 100
45 / 100
55 / 100

Machinability Rating (AISI 1212 = 100 %)

30%
62%
50%
56%

Weldability

15 / 100
40 / 100
25 / 100
25 / 100

Formability (cold)

10 / 100
40 / 100
25 / 100
45 / 100

Castability

30 / 100
35 / 100
40 / 100

Brazeability / Solderability

30 / 100
55 / 100
55 / 100
55 / 100

Polishability

70 / 100
60 / 100
60 / 100
70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

30 MJ/kg12,898 BTU/lb
32 MJ/kg13,758 BTU/lb
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
2.3 kg CO₂/kg
2.2 kg CO₂/kg

Embodied Water

60 L/kg7.2 gal/lb
55 L/kg6.6 gal/lb
60 L/kg7.2 gal/lb
60 L/kg7.2 gal/lb

Typical Recycled Content

30%
30%
30%
35%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

226 kN·m/kg
88 kN·m/kg
110 kN·m/kg
92 kN·m/kg

Specific Stiffness (E / density)

26.3 MN·m/kg
26.1 MN·m/kg
26.1 MN·m/kg
26.1 MN·m/kg

Modulus of Resilience

6,401 kJ/m³
562 kJ/m³
660 kJ/m³
184 kJ/m³

Thermal Diffusivity

11.9 mm²/s
11.5 mm²/s
11.5 mm²/s
12 mm²/s

Thermal Shock Resistance Index

32
12
15
13

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 scale4140415051609255

Manufacturing and finishing

Capability9255414041505160
CNC machiningYesYesYes
Sheet metalYesYesYes
Casting & forgingYes
Default conditionHRHRAnnealed
Relative cost$ Budget$$ Standard$$$ Premium$$$ Premium
Min. machined wall0.8 mm0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µmRa 1.6 µm
AlCrNYesYesYes
AlTiNYesYesYes
Black OxideYesYesYes
CVD Al2O3YesYesYes
CVD TiCNYesYesYes
CVD TiNYesYesYes
CerakoteYesYesYes
Chrome PlatingYesYesYes
CrNYesYesYes
DLCYesYesYes
E-CoatingYesYesYes
HVOF CoatingYesYesYes
Hot-Dip GalvanizingYesYesYes
MoS2YesYesYes
Multilayer CVDYesYesYes
Nickel PlatingYesYesYes
PTFE CoatingYesYesYes
PaintingYesYesYes

They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 9255 and 4140 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.