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Steel 12CrMo4 +A vs 12CrMo4 +C

Steel · 12CrMo4 temper comparison

12CrMo4 +A and 12CrMo4 +C are two conditions of the same steel grade, 12CrMo4: +A (annealed) versus +C (cold drawn). The chemistry is identical, so every difference below comes from the condition. 12CrMo4 +C is the stronger of the two: yield strength 520 MPa (75.4 ksi) against 300 MPa (43.5 ksi) for 12CrMo4 +A, about 73% more; tensile strength follows at 620 MPa (89.9 ksi) vs 480 MPa (69.6 ksi). In exchange, 12CrMo4 +A is the more ductile: elongation 27% versus 12% for 12CrMo4 +C, and 12CrMo4 +C is harder (195 HB vs 150 HB). 12CrMo4 +A runs hotter in service (500°C vs 400°C continuous).

12CrMo4 +AChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

12CrMo4 +CChoose it when strength drives the design.

12CrMo4 +A vs 12CrMo4 +C: properties

12CrMo4 +A12CrMo4 +C

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

480 MPa69.6 ksi
620 MPa89.9 ksi

Yield Strength (0.2% offset)

300 MPa43.5 ksi
520 MPa75.4 ksi

Elongation at Break

27%
12%

Reduction in Area

62%
45%

Compressive Strength

300 MPa43.5 ksi
540 MPa78.3 ksi

Shear Strength

300 MPa43.5 ksi
380 MPa55.1 ksi

Fatigue Strength (Endurance Limit)

225 MPa32.6 ksi
280 MPa40.6 ksi

Fracture Toughness (K_IC)

130 MPa·√m118 ksi·√in
90 MPa·√m81.9 ksi·√in

Charpy V-Notch Impact (RT)

110 J81.1 ft·lbf
45 J33.2 ft·lbf

Hardness, Brinell

150 HB
195 HB

Hardness, Rockwell B

80 HRB
92 HRB

Hardness, Vickers

155 HV
205 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,450°C2,642 °F · Liquidus Temperature 1,510°C2,750 °F

Thermal

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

Max Service Temperature (continuous)

500°C932 °F
400°C752 °F

Same in both: Thermal Conductivity 42 W/m·K24.3 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.3 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

7.8 % IACS
7.7 % IACS

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 µΩ·in
2.24×10⁻⁷ Ω·m8.82 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 13 / 100

Manufacturability

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

Machinability

62 / 100
63 / 100

Machinability Rating (AISI 1212 = 100 %)

66%
68%

Weldability

72 / 100
65 / 100

Formability (cold)

68 / 100
40 / 100

Same in both: Brazeability / Solderability 55 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 29 MJ/kg12,468 BTU/lb · Embodied Carbon (primary production) 2.2 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb · Typical Recycled Content 25%

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 scale12CrMo4

12CrMo4 +A vs 12CrMo4 +C — frequently asked

Is 12CrMo4 +C stronger than 12CrMo4 +A?

Yes. 12CrMo4 +C has a typical yield strength of 520 MPa (75.4 ksi) against 300 MPa (43.5 ksi) for 12CrMo4 +A — about 73% more. Tensile strength is 620 MPa (89.9 ksi) vs 480 MPa (69.6 ksi).

Which condition does FabDigit quote by default, +A or +C?

+N is the default 12CrMo4 condition in the FabDigit quote flow (neither +A nor +C). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.

Which welds better, 12CrMo4 +A or 12CrMo4 +C?

12CrMo4 +A. Its weldability rates very good (72/100) against good (65/100) for 12CrMo4 +C.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 12CrMo4 +A and 12CrMo4 +C 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.