FabDigit

40Cr vs 4130 and 2 more: properties

40Cr413025CrMo41340

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

211 GPa30.6 Msi
205 GPa29.7 Msi
210 GPa30.5 Msi
205 GPa29.7 Msi

Shear Modulus

81 GPa11.7 Msi
80 GPa11.6 Msi
80 GPa11.6 Msi
80 GPa11.6 Msi

Tensile Strength (Ultimate)

720 MPa104 ksi
700 MPa102 ksi
870 MPa126 ksi
745 MPa108 ksi

Yield Strength (0.2% offset)

430 MPa62.4 ksi
440 MPa63.8 ksi
650 MPa94.3 ksi
470 MPa68.2 ksi

Elongation at Break

16%
22%
16%
20%

Reduction in Area

45%
50%
50%
50%

Compressive Strength

430 MPa62.4 ksi
480 MPa69.6 ksi
660 MPa95.7 ksi

Shear Strength

430 MPa62.4 ksi
440 MPa63.8 ksi
520 MPa75.4 ksi
450 MPa65.3 ksi

Fatigue Strength (Endurance Limit)

330 MPa47.9 ksi
330 MPa47.9 ksi
450 MPa65.3 ksi
350 MPa50.8 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
110 MPa·√m100 ksi·√in
90 MPa·√m81.9 ksi·√in

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
55 J40.6 ft·lbf
60 J44.3 ft·lbf
40 J29.5 ft·lbf

Hardness, Brinell

210 HB
210 HB
270 HB
217 HB

Hardness, Rockwell B

94 HRB
95 HRB
96 HRB

Hardness, Rockwell C

16 HRC
28 HRC

Hardness, Vickers

228 HV
285 HV

Same in both: Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,425°C2,597 °F
1,432°C2,610 °F
1,420°C2,588 °F
1,425°C2,597 °F

Liquidus Temperature

1,495°C2,723 °F
1,510°C2,750 °F
1,500°C2,732 °F
1,495°C2,723 °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
42.7 W/m·K24.7 BTU/hr·ft·°F
42 W/m·K24.3 BTU/hr·ft·°F
44 W/m·K25.4 BTU/hr·ft·°F

Specific Heat Capacity

470 J/kg·K0.11 BTU/lb·°F
477 J/kg·K0.11 BTU/lb·°F
460 J/kg·K0.11 BTU/lb·°F
475 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

12.5 µm/m·K6.9 µin/in·°F
12.2 µm/m·K6.8 µin/in·°F
12.3 µm/m·K6.8 µin/in·°F
12.2 µm/m·K6.8 µin/in·°F

Latent Heat of Fusion

250 J/g107 BTU/lb
272 J/g117 BTU/lb
250 J/g107 BTU/lb
250 J/g107 BTU/lb

Max Service Temperature (continuous)

400°C752 °F
400°C752 °F
500°C932 °F
400°C752 °F

Min Service Temperature

-30°C-22 °F
-50°C-58 °F
-40°C-40 °F
-30°C-22 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

8 % IACS
7.7 % IACS
7.8 % IACS
7.8 % IACS

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 µΩ·in
2.23×10⁻⁷ Ω·m8.78 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)

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

Corrosion Resistance

12 / 100
14 / 100
13 / 100
10 / 100

Manufacturability

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

Machinability

55 / 100
55 / 100
55 / 100
50 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
60%
60%
55%

Weldability

45 / 100
65 / 100
65 / 100
40 / 100

Formability (cold)

40 / 100
45 / 100
45 / 100
40 / 100

Brazeability / Solderability

55 / 100
70 / 100
60 / 100
55 / 100

Polishability

60 / 100
60 / 100
65 / 100
60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

26 MJ/kg11,178 BTU/lb
30 MJ/kg12,898 BTU/lb
31 MJ/kg13,328 BTU/lb
30 MJ/kg12,898 BTU/lb

Embodied Carbon (primary production)

2 kg CO₂/kg
2.3 kg CO₂/kg
2.2 kg CO₂/kg
2.2 kg CO₂/kg

Embodied Water

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

Typical Recycled Content

35%
30%
30%
30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

92 kN·m/kg
89 kN·m/kg
111 kN·m/kg
95 kN·m/kg

Specific Stiffness (E / density)

26.9 MN·m/kg
26.1 MN·m/kg
26.8 MN·m/kg
26.1 MN·m/kg

Modulus of Resilience

438 kJ/m³
472 kJ/m³
1,006 kJ/m³
539 kJ/m³

Thermal Diffusivity

11.9 mm²/s
11.4 mm²/s
11.6 mm²/s
11.8 mm²/s

Thermal Shock Resistance Index

12
12
14
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 scale413040Cr25CrMo41340

Manufacturing and finishing

Capability40Cr413025CrMo41340
Default conditionHRHRQ&THR
Relative cost$$ Standard$$ Standard$$ Standard$$ Standard
Min. machined wall0.8 mm0.8 mm0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µmRa 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.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 40Cr and 4130 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.