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Steel 12CrNi3A-HR vs 12CrNi3A-QT

Steel · 12CrNi3A temper comparison

12CrNi3A-HR and 12CrNi3A-QT are two conditions of the same steel grade, 12CrNi3A: HR (hot rolled) versus QT (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. 12CrNi3A-QT is the stronger of the two: yield strength 785 MPa (114 ksi) against 500 MPa (72.5 ksi) for 12CrNi3A-HR, about 57% more; tensile strength follows at 980 MPa (142 ksi) vs 780 MPa (113 ksi). In exchange, 12CrNi3A-HR is the more ductile: elongation 16% versus 13% for 12CrNi3A-QT, and 12CrNi3A-QT is harder (300 HB vs 235 HB). 12CrNi3A-HR runs hotter in service (350°C vs 200°C continuous). On the shop floor, 12CrNi3A-HR welds better (45 vs 35 out of 100).

12CrNi3A-HRChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

12CrNi3A-QTChoose it when strength drives the design.

12CrNi3A-HR vs 12CrNi3A-QT: properties

12CrNi3A-HR12CrNi3A-QT

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

780 MPa113 ksi
980 MPa142 ksi

Yield Strength (0.2% offset)

500 MPa72.5 ksi
785 MPa114 ksi

Elongation at Break

16%
13%

Reduction in Area

50%
56%

Compressive Strength

505 MPa73.2 ksi
790 MPa115 ksi

Shear Strength

470 MPa68.2 ksi
590 MPa85.6 ksi

Fatigue Strength (Endurance Limit)

350 MPa50.8 ksi
470 MPa68.2 ksi

Fracture Toughness (K_IC)

85 MPa·√m77.4 ksi·√in
100 MPa·√m91 ksi·√in

Charpy V-Notch Impact (RT)

55 J40.6 ft·lbf
80 J59 ft·lbf

Hardness, Brinell

235 HB
300 HB

Hardness, Rockwell C

21 HRC
31 HRC

Hardness, Vickers

247 HV
315 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 165 GPa23.9 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) 1,420°C2,588 °F · Liquidus Temperature 1,490°C2,714 °F

Thermal

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

Thermal Conductivity

37 W/m·K21.4 BTU/hr·ft·°F
34 W/m·K19.6 BTU/hr·ft·°F

Max Service Temperature (continuous)

350°C662 °F
200°C392 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.8 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -70°C-94 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

6.2 % IACS
5.7 % IACS

Electrical Resistivity

2.8×10⁻⁷ Ω·m11 µΩ·in
3×10⁻⁷ Ω·m11.8 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 13 / 100

Manufacturability

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

Machinability

45 / 100
40 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
40%

Weldability

45 / 100
35 / 100

Formability (cold)

35 / 100
22 / 100

Same in both: Brazeability / Solderability 55 / 100 · Polishability 68 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 32 MJ/kg13,758 BTU/lb · Embodied Carbon (primary production) 2.4 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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale12CrNi3A

12CrNi3A-HR vs 12CrNi3A-QT — frequently asked

Is 12CrNi3A-QT stronger than 12CrNi3A-HR?

Yes. 12CrNi3A-QT has a typical yield strength of 785 MPa (114 ksi) against 500 MPa (72.5 ksi) for 12CrNi3A-HR — about 57% more. Tensile strength is 980 MPa (142 ksi) vs 780 MPa (113 ksi).

Which condition does FabDigit quote by default, HR or QT?

QT is the default 12CrNi3A condition in the FabDigit quote flow. 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, 12CrNi3A-HR or 12CrNi3A-QT?

12CrNi3A-HR, by a small margin. Both rate fair for machinability — 45/100 against 40/100 for 12CrNi3A-QT; for welding the order is 12CrNi3A-HR first (fair, 45/100) then 12CrNi3A-QT (fair, 35/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 12CrNi3A-HR and 12CrNi3A-QT 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.