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Steel 31CrMoV9 Q&T vs 31CrMoV9 Q&T 100-160

Steel · 31CrMoV9 temper comparison

31CrMoV9 Q&T and 31CrMoV9 Q&T 100-160 are two conditions of the same steel grade, 31CrMoV9: Q&T (quenched and tempered) versus Q&T 100-160 (+QT). The chemistry is identical, so every difference below comes from the condition. 31CrMoV9 Q&T is the stronger of the two: yield strength 880 MPa (128 ksi) against 680 MPa (98.6 ksi) for 31CrMoV9 Q&T 100-160, about 29% more; tensile strength follows at 1,100 MPa (160 ksi) vs 900 MPa (131 ksi). In exchange, 31CrMoV9 Q&T 100-160 is the more ductile: elongation 14% versus 12% for 31CrMoV9 Q&T, and 31CrMoV9 Q&T is harder (330 HB vs 270 HB).

31CrMoV9 Q&TChoose it when strength drives the design.

31CrMoV9 Q&T 100-160Choose it when the part is bent, formed or impact-loaded.

31CrMoV9 Q&T vs 31CrMoV9 Q&T 100-160: properties

31CrMoV9 Q&T31CrMoV9 Q&T 100-160

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

1,100 MPa160 ksi
900 MPa131 ksi

Yield Strength (0.2% offset)

880 MPa128 ksi
680 MPa98.6 ksi

Elongation at Break

12%
14%

Reduction in Area

45%
55%

Compressive Strength

900 MPa131 ksi
700 MPa102 ksi

Shear Strength

660 MPa95.7 ksi
540 MPa78.3 ksi

Fatigue Strength (Endurance Limit)

510 MPa74 ksi
430 MPa62.4 ksi

Fracture Toughness (K_IC)

75 MPa·√m68.3 ksi·√in
85 MPa·√m77.4 ksi·√in

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
50 J36.9 ft·lbf

Hardness, Brinell

330 HB
270 HB

Hardness, Rockwell C

34 HRC
27 HRC

Hardness, Vickers

345 HV
285 HV

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

Thermal

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

Thermal Conductivity

36 W/m·K20.8 BTU/hr·ft·°F
37 W/m·K21.4 BTU/hr·ft·°F

Same in both: Specific Heat Capacity 465 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 · Max Service Temperature (continuous) 450°C842 °F · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Corrosion Resistance 16 / 100

Manufacturability

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

Machinability

40 / 100
48 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
52%

Same in both: Weldability 20 / 100 · Formability (cold) 20 / 100 · Castability 25 / 100 · Brazeability / Solderability 45 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 30 MJ/kg12,898 BTU/lb · Embodied Carbon (primary production) 2.3 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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale31CrMoV9

31CrMoV9 Q&T vs 31CrMoV9 Q&T 100-160 — frequently asked

Is 31CrMoV9 Q&T stronger than 31CrMoV9 Q&T 100-160?

Yes. 31CrMoV9 Q&T has a typical yield strength of 880 MPa (128 ksi) against 680 MPa (98.6 ksi) for 31CrMoV9 Q&T 100-160 — about 29% more. Tensile strength is 1,100 MPa (160 ksi) vs 900 MPa (131 ksi).

Which condition does FabDigit quote by default, Q&T or Q&T 100-160?

Q&T is the default 31CrMoV9 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, 31CrMoV9 Q&T or 31CrMoV9 Q&T 100-160?

31CrMoV9 Q&T 100-160, by a small margin. Both rate fair for machinability — 48/100 against 40/100 for 31CrMoV9 Q&T.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 31CrMoV9 Q&T and 31CrMoV9 Q&T 100-160 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.