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Steel 40Cr Annealed vs 40Cr-CR

Steel · 40Cr temper comparison

40Cr Annealed and 40Cr-CR are two conditions of the same steel grade, 40Cr: Annealed versus CR (cold rolled). The chemistry is identical, so every difference below comes from the condition. 40Cr-CR is the stronger of the two: yield strength 620 MPa (89.9 ksi) against 400 MPa (58 ksi) for 40Cr Annealed, about 55% more; tensile strength follows at 800 MPa (116 ksi) vs 680 MPa (98.6 ksi). In exchange, 40Cr Annealed is the more ductile: elongation 22% versus 10% for 40Cr-CR, and 40Cr-CR is harder (235 HB vs 187 HB). 40Cr Annealed runs hotter in service (400°C vs 300°C continuous). On the shop floor, 40Cr Annealed machines more easily (65 vs 55 out of 100) and 40Cr Annealed welds better (50 vs 40 out of 100).

40Cr AnnealedChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

40Cr-CRChoose it when strength drives the design.

40Cr Annealed vs 40Cr-CR: properties

40Cr Annealed40Cr-CR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

211 GPa30.6 Msi
210 GPa30.5 Msi

Tensile Strength (Ultimate)

680 MPa98.6 ksi
800 MPa116 ksi

Yield Strength (0.2% offset)

400 MPa58 ksi
620 MPa89.9 ksi

Elongation at Break

22%
10%

Reduction in Area

52%
40%

Compressive Strength

430 MPa62.4 ksi
620 MPa89.9 ksi

Shear Strength

430 MPa62.4 ksi
480 MPa69.6 ksi

Fatigue Strength (Endurance Limit)

310 MPa45 ksi
360 MPa52.2 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
50 MPa·√m45.5 ksi·√in

Charpy V-Notch Impact (RT)

55 J40.6 ft·lbf
25 J18.4 ft·lbf

Hardness, Brinell

187 HB
235 HB

Hardness, Rockwell B

94 HRB
99 HRB

Hardness, Rockwell C

16 HRC
22 HRC

Same in both: 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) 1,425°C2,597 °F · Liquidus Temperature 1,495°C2,723 °F

Thermal

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

Max Service Temperature (continuous)

400°C752 °F
300°C572 °F

Same in both: Thermal Conductivity 44 W/m·K25.4 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.5 µm/m·K6.9 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 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 12 / 100

Manufacturability

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

Machinability

65 / 100
55 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
60%

Weldability

50 / 100
40 / 100

Formability (cold)

55 / 100
30 / 100

Same in both: Brazeability / Solderability 55 / 100 · Polishability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 26 MJ/kg11,178 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb · Typical Recycled Content 35%

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 scale40Cr

40Cr Annealed vs 40Cr-CR — frequently asked

Is 40Cr-CR stronger than 40Cr Annealed?

Yes. 40Cr-CR has a typical yield strength of 620 MPa (89.9 ksi) against 400 MPa (58 ksi) for 40Cr Annealed — about 55% more. Tensile strength is 800 MPa (116 ksi) vs 680 MPa (98.6 ksi).

Which condition does FabDigit quote by default, Annealed or CR?

HR is the default 40Cr condition in the FabDigit quote flow (neither Annealed nor CR). 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, 40Cr Annealed or 40Cr-CR?

40Cr Annealed, by a small margin. Both rate good for machinability — 65/100 against 55/100 for 40Cr-CR; for welding the order is 40Cr Annealed first (fair, 50/100) then 40Cr-CR (fair, 40/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 40Cr Annealed and 40Cr-CR 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.