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Steel 30CrMoV9 vs AR400

Steel · grade comparison

Steel 30CrMoV9 and AR400 are both steel grades. AR400 is the stronger of the two: yield strength 1,050 MPa (152 ksi) against 750 MPa (109 ksi) for 30CrMoV9, about 40% more; tensile strength follows at 1,250 MPa (181 ksi) vs 1,000 MPa (145 ksi). AR400 is harder — 400 HB against 305 HB for 30CrMoV9 — which matters for wear surfaces and threads. 30CrMoV9 runs hotter in service (450°C vs 250°C continuous) and AR400 conducts heat better (42 W/m·K vs 34 W/m·K). On the shop floor, 30CrMoV9 machines more easily (fair vs poor), AR400 welds better (good vs poor), and 30CrMoV9 sits in a lower cost tier (standard, $$) than AR400 (premium, $$$).

30CrMoV9Choose it when the part sees heat, or when the part is machined in volume.

AR400Choose it when strength drives the design, or when surface hardness matters.

30CrMoV9 vs AR400: properties

30CrMoV9AR400

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

210 GPa30.5 Msi
205 GPa29.7 Msi

Shear Modulus

81 GPa11.7 Msi
80 GPa11.6 Msi

Bulk Modulus

165 GPa23.9 Msi
160 GPa23.2 Msi

Tensile Strength (Ultimate)

1,000 MPa145 ksi
1,250 MPa181 ksi

Yield Strength (0.2% offset)

750 MPa109 ksi
1,050 MPa152 ksi

Reduction in Area

45%
40%

Compressive Strength

760 MPa110 ksi
1,100 MPa160 ksi

Shear Strength

620 MPa89.9 ksi
780 MPa113 ksi

Fatigue Strength (Endurance Limit)

500 MPa72.5 ksi
520 MPa75.4 ksi

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

305 HB
400 HB

Hardness, Rockwell C

31 HRC
43 HRC

Hardness, Vickers

320 HV
420 HV

Same in both: Poisson's Ratio 0.29 · Elongation at Break 11% · Fracture Toughness (K_IC) 70 MPa·√m63.7 ksi·√in

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,430°C2,606 °F
1,420°C2,588 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Liquidus Temperature 1,500°C2,732 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

34 W/m·K19.6 BTU/hr·ft·°F
42 W/m·K24.3 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

11.5 µm/m·K6.4 µin/in·°F
12 µm/m·K6.7 µin/in·°F

Max Service Temperature (continuous)

450°C842 °F
250°C482 °F

Min Service Temperature

-40°C-40 °F
-20°C-4 °F

Same in both: Latent Heat of Fusion 250 J/g107 BTU/lb

Electrical

Conductivity and insulation.

Electrical Conductivity

7.8 % IACS
8 % IACS

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)

-0.6 V
—

Corrosion Resistance

18 / 100
12 / 100

Manufacturability

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

Machinability

40 / 100
22 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
20%

Weldability

22 / 100
55 / 100

Formability (cold)

20 / 100
25 / 100

Castability

20 / 100
—

Brazeability / Solderability

40 / 100
20 / 100

Polishability

65 / 100
55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

34 MJ/kg14,617 BTU/lb
28 MJ/kg12,038 BTU/lb

Embodied Carbon (primary production)

2.4 kg CO₂/kg
2.3 kg CO₂/kg

Embodied Water

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

Typical Recycled Content

30%
25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

127 kN·m/kg
159 kN·m/kg

Specific Stiffness (E / density)

26.8 MN·m/kg
26.1 MN·m/kg

Modulus of Resilience

1,339 kJ/m³
2,689 kJ/m³

Thermal Diffusivity

9.4 mm²/s
11.4 mm²/s

Thermal Shock Resistance Index

14
21

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 scaleAR40030CrMoV9

Manufacturing and finishing

Capability30CrMoV9AR400
CNC machining—Yes
Sheet metal—Yes
Default condition—Q&T
Relative cost$$ Standard$$$ 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.

30CrMoV9 vs AR400 — frequently asked

Is AR400 stronger than 30CrMoV9?

Yes. AR400 has a typical yield strength of 1,050 MPa (152 ksi) against 750 MPa (109 ksi) for 30CrMoV9 — about 40% more. Tensile strength is 1,250 MPa (181 ksi) vs 1,000 MPa (145 ksi).

Which is cheaper, 30CrMoV9 or AR400?

30CrMoV9 is the lower-cost material: it sits in the standard tier ($$) while AR400 is premium ($$$). 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, 30CrMoV9 or AR400?

30CrMoV9. Its machinability rates fair (40/100) against poor (22/100) for AR400; for welding the order is AR400 first (good, 55/100) then 30CrMoV9 (poor, 22/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 30CrMoV9 and AR400 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.