FabDigitFabDigit

Steel 40Cr Normalized vs 40Cr Q&T

Steel · 40Cr temper comparison

40Cr Normalized and 40Cr Q&T are two conditions of the same steel grade, 40Cr: Normalized versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. 40Cr Q&T is the stronger of the two: yield strength 830 MPa (120 ksi) against 500 MPa (72.5 ksi) for 40Cr Normalized, about 66% more; tensile strength follows at 1,020 MPa (148 ksi) vs 800 MPa (116 ksi). In exchange, 40Cr Normalized is the more ductile: elongation 18% versus 12% for 40Cr Q&T, and 40Cr Q&T is harder (300 HB vs 229 HB). On the shop floor, 40Cr Normalized machines more easily (good vs fair) and 40Cr Normalized welds better (45 vs 35 out of 100).

40Cr NormalizedChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

40Cr Q&TChoose it when strength drives the design.

40Cr Normalized vs 40Cr Q&T: properties

40Cr Normalized40Cr Q&T

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

800 MPa116 ksi
1,020 MPa148 ksi

Yield Strength (0.2% offset)

500 MPa72.5 ksi
830 MPa120 ksi

Elongation at Break

18%
12%

Reduction in Area

48%
50%

Compressive Strength

500 MPa72.5 ksi
430 MPa62.4 ksi

Shear Strength

480 MPa69.6 ksi
610 MPa88.5 ksi

Fatigue Strength (Endurance Limit)

370 MPa53.7 ksi
480 MPa69.6 ksi

Fracture Toughness (K_IC)

58 MPa·√m52.8 ksi·√in
65 MPa·√m59.2 ksi·√in

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
55 J40.6 ft·lbf

Hardness, Brinell

229 HB
300 HB

Hardness, Rockwell B

98 HRB
94 HRB

Hardness, Rockwell C

20 HRC
31 HRC

Same in both: Elastic (Young's) Modulus 211 GPa30.6 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) 1,425°C2,597 °F · Liquidus Temperature 1,495°C2,723 °F

Thermal

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

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 · Max Service Temperature (continuous) 400°C752 °F · 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

58 / 100
42 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
45%

Weldability

45 / 100
35 / 100

Formability (cold)

38 / 100
40 / 100

Polishability

60 / 100
70 / 100

Same in both: Brazeability / Solderability 55 / 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 Normalized vs 40Cr Q&T — frequently asked

Is 40Cr Q&T stronger than 40Cr Normalized?

Yes. 40Cr Q&T has a typical yield strength of 830 MPa (120 ksi) against 500 MPa (72.5 ksi) for 40Cr Normalized — about 66% more. Tensile strength is 1,020 MPa (148 ksi) vs 800 MPa (116 ksi).

Which condition does FabDigit quote by default, Normalized or Q&T?

HR is the default 40Cr condition in the FabDigit quote flow (neither Normalized nor Q&T). 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 Normalized or 40Cr Q&T?

40Cr Normalized. Its machinability rates good (58/100) against fair (42/100) for 40Cr Q&T; for welding the order is 40Cr Normalized first (fair, 45/100) then 40Cr Q&T (fair, 35/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 40Cr Normalized and 40Cr Q&T 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.