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Steel A2 vs Cr12

Steel · grade comparison

Steel A2 and Cr12 are both steel grades, both tool steel. Cr12 is the stronger of the two: tensile strength 820 MPa (119 ksi) against 740 MPa (107 ksi) for A2, about 11% more. In exchange, A2 is the more ductile: elongation 22% versus 12% for Cr12, and Cr12 is harder (240 HB vs 217 HB). A2 runs hotter in service (425°C vs 200°C continuous) and A2 conducts heat better (26 W/m·K vs 20 W/m·K). On the shop floor, A2 machines more easily (fair vs poor).

A2Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

Cr12Choose it when strength drives the design.

A2 vs Cr12: properties

A2Cr12

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

203 GPa29.4 Msi
210 GPa30.5 Msi

Shear Modulus

78 GPa11.3 Msi
81 GPa11.7 Msi

Tensile Strength (Ultimate)

740 MPa107 ksi
820 MPa119 ksi

Yield Strength (0.2% offset)

470 MPa68.2 ksi
480 MPa69.6 ksi

Elongation at Break

22%
12%

Reduction in Area

45%
20%

Compressive Strength

500 MPa72.5 ksi
900 MPa131 ksi

Shear Strength

450 MPa65.3 ksi
—

Fatigue Strength (Endurance Limit)

330 MPa47.9 ksi
—

Charpy V-Notch Impact (RT)

30 J22.1 ft·lbf
10 J7.4 ft·lbf

Hardness, Brinell

217 HB
240 HB

Hardness, Rockwell B

96 HRB
—

Hardness, Vickers

230 HV
250 HV

Hardness, Rockwell C

—
22 HRC

Same in both: Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.28

Physical

Density and transition temperatures.

Density

7.86 g/cm³0.28 lb/in³
7.7 g/cm³0.28 lb/in³

Melting Point (Solidus)

1,420°C2,588 °F
1,400°C2,552 °F

Liquidus Temperature

1,465°C2,669 °F
1,450°C2,642 °F

Thermal

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

Thermal Conductivity

26 W/m·K15 BTU/hr·ft·°F
20 W/m·K11.6 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

10.7 µm/m·K5.9 µin/in·°F
11.5 µm/m·K6.4 µin/in·°F

Max Service Temperature (continuous)

425°C797 °F
200°C392 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 2.7 % IACS · Electrical Resistivity 6.5×10⁻⁷ Ω·m25.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

20 / 100
24 / 100

Manufacturability

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

Machinability

45 / 100
32 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
30%

Weldability

20 / 100
12 / 100

Formability (cold)

35 / 100
12 / 100

Castability

20 / 100
25 / 100

Brazeability / Solderability

40 / 100
35 / 100

Same in both: Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Water

65 L/kg7.8 gal/lb
60 L/kg7.2 gal/lb

Typical Recycled Content

35%
45%

Same in both: Embodied Energy (primary production) 36 MJ/kg15,477 BTU/lb · Embodied Carbon (primary production) 2.6 kg CO₂/kg

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

94 kN·m/kg
106 kN·m/kg

Specific Stiffness (E / density)

25.8 MN·m/kg
27.3 MN·m/kg

Modulus of Resilience

544 kJ/m³
549 kJ/m³

Thermal Diffusivity

7.2 mm²/s
5.6 mm²/s

Thermal Shock Resistance Index

9
7

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 scaleA2Cr12

Manufacturing and finishing

CapabilityA2Cr12
Default conditionAnnealedAnnealed
Relative cost$$$ Premium$$$ Premium
Min. machined wall0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µm

Both are offered for CNC machining. 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.

A2 vs Cr12 — frequently asked

Is Cr12 stronger than A2?

Yes. Cr12 has a typical tensile strength of 820 MPa (119 ksi) against 740 MPa (107 ksi) for A2 — about 11% more.

Which is cheaper, A2 or Cr12?

Both sit in the same relative cost tier ($$$, premium); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which is easier to machine, A2 or Cr12?

A2. Its machinability rates fair (45/100) against poor (32/100) for Cr12; for welding the order is A2 first (poor, 20/100) then Cr12 (not recommended, 12/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in A2 and Cr12 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.