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Steel 4330-CD vs 4330 Q&T

Steel · 4330 temper comparison

4330-CD and 4330 Q&T are two conditions of the same steel grade, 4330: CD (cold drawn) versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. 4330 Q&T is the stronger of the two: yield strength 965 MPa (140 ksi) against 790 MPa (115 ksi) for 4330-CD, about 22% more; tensile strength follows at 1,100 MPa (160 ksi) vs 950 MPa (138 ksi). 4330 Q&T is the more ductile: elongation 16% versus 12% for 4330-CD, and 4330 Q&T is harder (321 HB vs 285 HB). 4330 Q&T runs hotter in service (370°C vs 300°C continuous).

4330 Q&TChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.

4330-CD vs 4330 Q&T: properties

4330-CD4330 Q&T

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

950 MPa138 ksi
1,100 MPa160 ksi

Yield Strength (0.2% offset)

790 MPa115 ksi
965 MPa140 ksi

Elongation at Break

12%
16%

Reduction in Area

40%
50%

Compressive Strength

855 MPa124 ksi
810 MPa117 ksi

Shear Strength

570 MPa82.7 ksi
540 MPa78.3 ksi

Fatigue Strength (Endurance Limit)

430 MPa62.4 ksi
520 MPa75.4 ksi

Fracture Toughness (K_IC)

115 MPa·√m105 ksi·√in
110 MPa·√m100 ksi·√in

Charpy V-Notch Impact (RT)

28 J20.7 ft·lbf
60 J44.3 ft·lbf

Hardness, Brinell

285 HB
321 HB

Hardness, Rockwell C

29 HRC
34 HRC

Hardness, Vickers

300 HV
275 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.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,500°C2,732 °F

Thermal

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

Thermal Conductivity

42 W/m·K24.3 BTU/hr·ft·°F
44 W/m·K25.4 BTU/hr·ft·°F

Max Service Temperature (continuous)

300°C572 °F
370°C698 °F

Same in both: Specific Heat Capacity 470 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 270 J/g116 BTU/lb · Min Service Temperature -60°C-76 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 µΩ·in
2.15×10⁻⁷ Ω·m8.46 µΩ·in

Same in both: Electrical Conductivity 8 % IACS

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 14 / 100

Manufacturability

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

Machinability

52 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

55%
45%

Weldability

40 / 100
45 / 100

Formability (cold)

25 / 100
35 / 100

Same in both: Brazeability / Solderability 55 / 100 · Polishability 70 / 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 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 scale4330

4330-CD vs 4330 Q&T — frequently asked

Is 4330 Q&T stronger than 4330-CD?

Yes. 4330 Q&T has a typical yield strength of 965 MPa (140 ksi) against 790 MPa (115 ksi) for 4330-CD — about 22% more. Tensile strength is 1,100 MPa (160 ksi) vs 950 MPa (138 ksi).

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

HR is the default 4330 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, 4330-CD or 4330 Q&T?

4330-CD, by a small margin. Both rate fair for machinability — 52/100 against 45/100 for 4330 Q&T; for welding the order is 4330 Q&T first (fair, 45/100) then 4330-CD (fair, 40/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 4330-CD and 4330 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.