Steel 12CrMo4 +AR vs 12CrMo4 +NT
Steel · 12CrMo4 temper comparison
12CrMo4 +AR and 12CrMo4 +NT are two conditions of the same steel grade, 12CrMo4: +AR (hot rolled) versus +NT (normalized and tempered). The chemistry is identical, so every difference below comes from the condition. 12CrMo4 +AR is the stronger of the two: tensile strength 520 MPa (75.4 ksi) against 490 MPa (71.1 ksi) for 12CrMo4 +NT, about 6% more. In exchange, 12CrMo4 +NT is the more ductile: elongation 25% versus 22% for 12CrMo4 +AR, and 12CrMo4 +AR is harder (165 HB vs 148 HB). 12CrMo4 +NT runs hotter in service (530°C vs 480°C continuous).
12CrMo4 +ARChoose it when strength drives the design.
12CrMo4 +NTChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
12CrMo4 +AR vs 12CrMo4 +NT: 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
Fatigue Strength (Endurance Limit)
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
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) 12.3 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.
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) -0.61 V · Corrosion Resistance 13 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
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.
12CrMo4 +AR vs 12CrMo4 +NT — frequently asked
Is 12CrMo4 +AR stronger than 12CrMo4 +NT?
Yes. 12CrMo4 +AR has a typical tensile strength of 520 MPa (75.4 ksi) against 490 MPa (71.1 ksi) for 12CrMo4 +NT — about 6% more.
Which condition does FabDigit quote by default, +AR or +NT?
+N is the default 12CrMo4 condition in the FabDigit quote flow (neither +AR nor +NT). 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.
When should I choose 12CrMo4 +AR over 12CrMo4 +NT?
Pick 12CrMo4 +AR when strength drives the design. Pick 12CrMo4 +NT when the part is bent, formed or impact-loaded, or when the part sees heat.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 12CrMo4 +AR and 12CrMo4 +NT 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.