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Steel 40CrMoV4-6 +QT vs 40CrMoV4-6 +QT1100

Steel · 40CrMoV4-6 temper comparison

40CrMoV4-6 +QT and 40CrMoV4-6 +QT1100 are two conditions of the same steel grade, 40CrMoV4-6: +QT (quenched and tempered) versus +QT1100 (+QT high strength). The chemistry is identical, so every difference below comes from the condition. 40CrMoV4-6 +QT1100 is the stronger of the two: yield strength 1,000 MPa (145 ksi) against 800 MPa (116 ksi) for 40CrMoV4-6 +QT, about 25% more; tensile strength follows at 1,200 MPa (174 ksi) vs 1,000 MPa (145 ksi). In exchange, 40CrMoV4-6 +QT is the more ductile: elongation 14% versus 11% for 40CrMoV4-6 +QT1100, and 40CrMoV4-6 +QT1100 is harder (360 HB vs 300 HB). 40CrMoV4-6 +QT runs hotter in service (500°C vs 420°C continuous). On the shop floor, 40CrMoV4-6 +QT machines more easily (45 vs 35 out of 100).

40CrMoV4-6 +QTChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

40CrMoV4-6 +QT1100Choose it when strength drives the design.

40CrMoV4-6 +QT vs 40CrMoV4-6 +QT1100: properties

40CrMoV4-6 +QT40CrMoV4-6 +QT1100

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

1,000 MPa145 ksi
1,200 MPa174 ksi

Yield Strength (0.2% offset)

800 MPa116 ksi
1,000 MPa145 ksi

Elongation at Break

14%
11%

Reduction in Area

50%
45%

Fatigue Strength (Endurance Limit)

470 MPa68.2 ksi
550 MPa79.8 ksi

Fracture Toughness (K_IC)

80 MPa·√m72.8 ksi·√in
65 MPa·√m59.2 ksi·√in

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

300 HB
360 HB

Hardness, Rockwell C

32 HRC
38 HRC

Hardness, Vickers

315 HV
380 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 166 GPa24.1 Msi · Poisson's Ratio 0.29 · Compressive Strength 820 MPa119 ksi · Shear Strength 620 MPa89.9 ksi

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 1,480°C2,696 °F

Thermal

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

Max Service Temperature (continuous)

500°C932 °F
420°C788 °F

Same in both: Thermal Conductivity 40 W/m·K23.1 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.2 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -40°C-40 °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 12 / 100

Manufacturability

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

Machinability

45 / 100
35 / 100

Machinability Rating (AISI 1212 = 100 %)

50%
38%

Same in both: Weldability 25 / 100 · Formability (cold) 20 / 100 · Brazeability / Solderability 45 / 100 · Polishability 65 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 31 MJ/kg13,328 BTU/lb · Embodied Carbon (primary production) 2.1 kg CO₂/kg · Embodied Water 60 L/kg7.2 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 scale40CrMoV4-6

40CrMoV4-6 +QT vs 40CrMoV4-6 +QT1100 — frequently asked

Is 40CrMoV4-6 +QT1100 stronger than 40CrMoV4-6 +QT?

Yes. 40CrMoV4-6 +QT1100 has a typical yield strength of 1,000 MPa (145 ksi) against 800 MPa (116 ksi) for 40CrMoV4-6 +QT — about 25% more. Tensile strength is 1,200 MPa (174 ksi) vs 1,000 MPa (145 ksi).

Which condition does FabDigit quote by default, +QT or +QT1100?

+QT is the default 40CrMoV4-6 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, 40CrMoV4-6 +QT or 40CrMoV4-6 +QT1100?

40CrMoV4-6 +QT, by a small margin. Both rate fair for machinability — 45/100 against 35/100 for 40CrMoV4-6 +QT1100.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 40CrMoV4-6 +QT and 40CrMoV4-6 +QT1100 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.