Steel 12CrMo-A vs 12CrMo-HR
Steel · 12CrMo temper comparison
12CrMo-A and 12CrMo-HR are two conditions of the same steel grade, 12CrMo: A (solution annealed) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. 12CrMo-HR is the stronger of the two: yield strength 295 MPa (42.8 ksi) against 250 MPa (36.3 ksi) for 12CrMo-A, about 18% more; tensile strength follows at 490 MPa (71.1 ksi) vs 430 MPa (62.4 ksi). In exchange, 12CrMo-A is the more ductile: elongation 30% versus 24% for 12CrMo-HR, and 12CrMo-HR is harder (155 HB vs 130 HB). 12CrMo-A runs hotter in service (550°C vs 500°C continuous).
12CrMo-AChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
12CrMo-HRChoose it when strength drives the design.
12CrMo-A vs 12CrMo-HR: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
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 · Fatigue Strength (Endurance Limit) 225 MPa32.6 ksi
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)
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 µm/m·K6.7 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 7.8 % IACS · Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.62 V · Corrosion Resistance 16 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Formability (cold)
Same in both: Weldability 62 / 100 · Brazeability / Solderability 50 / 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) 2.3 kg CO₂/kg · Embodied Water 65 L/kg7.8 gal/lb · Typical Recycled Content 30%
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.
12CrMo-A vs 12CrMo-HR — frequently asked
Is 12CrMo-HR stronger than 12CrMo-A?
Yes. 12CrMo-HR has a typical yield strength of 295 MPa (42.8 ksi) against 250 MPa (36.3 ksi) for 12CrMo-A — about 18% more. Tensile strength is 490 MPa (71.1 ksi) vs 430 MPa (62.4 ksi).
Which condition does FabDigit quote by default, A or HR?
N+T is the default 12CrMo condition in the FabDigit quote flow (neither A nor HR). 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 is easier to machine, 12CrMo-A or 12CrMo-HR?
12CrMo-A, by a small margin. Both rate good for machinability — 65/100 against 56/100 for 12CrMo-HR.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 12CrMo-A and 12CrMo-HR 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.