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Steel 4150-CD vs 4150 Q&T

Steel · 4150 temper comparison

4150-CD and 4150 Q&T are two conditions of the same steel grade, 4150: CD (cold drawn) versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. 4150 Q&T is the stronger of the two: yield strength 1,105 MPa (160 ksi) against 830 MPa (120 ksi) for 4150-CD, about 33% more; tensile strength follows at 1,210 MPa (175 ksi) vs 945 MPa (137 ksi). 4150 Q&T is the more ductile: elongation 15% versus 10% for 4150-CD, and 4150 Q&T is harder (341 HB vs 277 HB). 4150 Q&T runs hotter in service (480°C vs 400°C continuous). On the shop floor, 4150-CD machines more easily (50 vs 35 out of 100) and 4150-CD welds better (28 vs 15 out of 100).

4150-CDChoose it when the part is machined in volume, or when it will be welded.

4150 Q&TChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.

4150-CD vs 4150 Q&T: properties

4150-CD4150 Q&T

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

945 MPa137 ksi
1,210 MPa175 ksi

Yield Strength (0.2% offset)

830 MPa120 ksi
1,105 MPa160 ksi

Elongation at Break

10%
15%

Reduction in Area

30%
55%

Shear Strength

570 MPa82.7 ksi
740 MPa107 ksi

Fatigue Strength (Endurance Limit)

440 MPa63.8 ksi
545 MPa79 ksi

Charpy V-Notch Impact (RT)

16 J11.8 ft·lbf
35 J25.8 ft·lbf

Hardness, Brinell

277 HB
341 HB

Hardness, Rockwell C

28 HRC
37 HRC

Hardness, Vickers

291 HV
360 HV

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Liquidus Temperature

1,471°C2,680 °F
1,490°C2,714 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,416°C2,581 °F

Thermal

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

Max Service Temperature (continuous)

400°C752 °F
480°C896 °F

Min Service Temperature

-25°C-13 °F
-40°C-40 °F

Same in both: Thermal Conductivity 42.6 W/m·K24.6 BTU/hr·ft·°F · Specific Heat Capacity 473 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.3 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb

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) -0.6 V · Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

50 / 100
35 / 100

Machinability Rating (AISI 1212 = 100 %)

55%
40%

Weldability

28 / 100
15 / 100

Formability (cold)

18 / 100
25 / 100

Polishability

62 / 100
60 / 100

Same in both: Castability 35 / 100 · Brazeability / Solderability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

30 MJ/kg12,898 BTU/lb
31 MJ/kg13,328 BTU/lb

Embodied Carbon (primary production)

2.2 kg CO₂/kg
2.3 kg CO₂/kg

Typical Recycled Content

25%
30%

Same in both: Embodied Water 60 L/kg7.2 gal/lb

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 scale4150

4150-CD vs 4150 Q&T — frequently asked

Is 4150 Q&T stronger than 4150-CD?

Yes. 4150 Q&T has a typical yield strength of 1,105 MPa (160 ksi) against 830 MPa (120 ksi) for 4150-CD — about 33% more. Tensile strength is 1,210 MPa (175 ksi) vs 945 MPa (137 ksi).

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

HR is the default 4150 condition in the FabDigit quote flow (neither CD 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, 4150-CD or 4150 Q&T?

4150-CD, by a small margin. Both rate fair for machinability — 50/100 against 35/100 for 4150 Q&T; for welding the order is 4150-CD first (poor, 28/100) then 4150 Q&T (poor, 15/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 4150-CD and 4150 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.