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Steel 7CrWVMoNb9-6-A vs 7CrWVMoNb9-6 Q+T

Steel · 7CrWVMoNb9-6 temper comparison

7CrWVMoNb9-6-A and 7CrWVMoNb9-6 Q+T are two conditions of the same steel grade, 7CrWVMoNb9-6: A (solution annealed) versus Q+T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. 7CrWVMoNb9-6 Q+T is the stronger of the two: yield strength 520 MPa (75.4 ksi) against 320 MPa (46.4 ksi) for 7CrWVMoNb9-6-A, about 63% more; tensile strength follows at 650 MPa (94.3 ksi) vs 500 MPa (72.5 ksi). In exchange, 7CrWVMoNb9-6-A is the more ductile: elongation 28% versus 21% for 7CrWVMoNb9-6 Q+T, and 7CrWVMoNb9-6 Q+T is harder (210 HB vs 155 HB). On the shop floor, 7CrWVMoNb9-6-A machines more easily (good vs fair).

7CrWVMoNb9-6-AChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

7CrWVMoNb9-6 Q+TChoose it when strength drives the design.

7CrWVMoNb9-6-A vs 7CrWVMoNb9-6 Q+T: properties

7CrWVMoNb9-6-A7CrWVMoNb9-6 Q+T

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

500 MPa72.5 ksi
650 MPa94.3 ksi

Yield Strength (0.2% offset)

320 MPa46.4 ksi
520 MPa75.4 ksi

Elongation at Break

28%
21%

Reduction in Area

68%
62%

Compressive Strength

320 MPa46.4 ksi
520 MPa75.4 ksi

Shear Strength

310 MPa45 ksi
400 MPa58 ksi

Fatigue Strength (Endurance Limit)

240 MPa34.8 ksi
310 MPa45 ksi

Fracture Toughness (K_IC)

150 MPa·√m137 ksi·√in
115 MPa·√m105 ksi·√in

Charpy V-Notch Impact (RT)

170 J125 ft·lbf
120 J88.5 ft·lbf

Hardness, Brinell

155 HB
210 HB

Hardness, Rockwell B

82 HRB
95 HRB

Hardness, Vickers

163 HV
220 HV

Same in both: Elastic (Young's) Modulus 213 GPa30.9 Msi · Shear Modulus 82 GPa11.9 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) 1,465°C2,669 °F · Liquidus Temperature 1,510°C2,750 °F

Thermal

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

Thermal Conductivity

32 W/m·K18.5 BTU/hr·ft·°F
29 W/m·K16.8 BTU/hr·ft·°F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 580°C1,076 °F · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

2.3×10⁻⁷ Ω·m9.06 µΩ·in
2.4×10⁻⁷ Ω·m9.45 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 20 / 100

Manufacturability

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

Machinability

60 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
50%

Weldability

65 / 100
58 / 100

Formability (cold)

60 / 100
35 / 100

Same in both: Brazeability / Solderability 40 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 32 MJ/kg13,758 BTU/lb · Embodied Carbon (primary production) 2.3 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 scale7CrWVMoNb9-6

7CrWVMoNb9-6-A vs 7CrWVMoNb9-6 Q+T — frequently asked

Is 7CrWVMoNb9-6 Q+T stronger than 7CrWVMoNb9-6-A?

Yes. 7CrWVMoNb9-6 Q+T has a typical yield strength of 520 MPa (75.4 ksi) against 320 MPa (46.4 ksi) for 7CrWVMoNb9-6-A — about 63% more. Tensile strength is 650 MPa (94.3 ksi) vs 500 MPa (72.5 ksi).

Which condition does FabDigit quote by default, A or Q+T?

N+T is the default 7CrWVMoNb9-6 condition in the FabDigit quote flow (neither A 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, 7CrWVMoNb9-6-A or 7CrWVMoNb9-6 Q+T?

7CrWVMoNb9-6-A. Its machinability rates good (60/100) against fair (45/100) for 7CrWVMoNb9-6 Q+T; for welding the order is 7CrWVMoNb9-6-A first (good, 65/100) then 7CrWVMoNb9-6 Q+T (good, 58/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 7CrWVMoNb9-6-A and 7CrWVMoNb9-6 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.