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Steel 38CrMoAlA-CD vs 38CrMoAlA Q&T

Steel · 38CrMoAlA temper comparison

38CrMoAlA-CD and 38CrMoAlA Q&T are two conditions of the same steel grade, 38CrMoAlA: CD (cold drawn) versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. 38CrMoAlA Q&T is the stronger of the two: yield strength 880 MPa (128 ksi) against 700 MPa (102 ksi) for 38CrMoAlA-CD, about 26% more; tensile strength follows at 1,030 MPa (149 ksi) vs 850 MPa (123 ksi). 38CrMoAlA Q&T is the more ductile: elongation 16% versus 10% for 38CrMoAlA-CD, and 38CrMoAlA Q&T is harder (310 HB vs 255 HB). 38CrMoAlA Q&T runs hotter in service (500°C vs 350°C continuous).

38CrMoAlA Q&TChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.

38CrMoAlA-CD vs 38CrMoAlA Q&T: properties

38CrMoAlA-CD38CrMoAlA Q&T

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

850 MPa123 ksi
1,030 MPa149 ksi

Yield Strength (0.2% offset)

700 MPa102 ksi
880 MPa128 ksi

Elongation at Break

10%
16%

Reduction in Area

38%
55%

Compressive Strength

720 MPa104 ksi
900 MPa131 ksi

Shear Strength

510 MPa74 ksi
640 MPa92.8 ksi

Fatigue Strength (Endurance Limit)

360 MPa52.2 ksi
470 MPa68.2 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
70 MPa·√m63.7 ksi·√in

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
80 J59 ft·lbf

Hardness, Brinell

255 HB
310 HB

Hardness, Rockwell C

25 HRC
32 HRC

Hardness, Vickers

268 HV
325 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 7.8 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

35 W/m·K20.2 BTU/hr·ft·°F
33 W/m·K19.1 BTU/hr·ft·°F

Max Service Temperature (continuous)

350°C662 °F
500°C932 °F

Same in both: Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.9 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

8 % IACS
7.8 % IACS

Electrical Resistivity

2.15×10⁻⁷ Ω·m8.46 µΩ·in
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
45 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
55%

Same in both: Weldability 20 / 100 · Formability (cold) 20 / 100 · Castability 25 / 100 · Brazeability / Solderability 35 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 34 MJ/kg14,617 BTU/lb · Embodied Carbon (primary production) 2.3 kg CO₂/kg · Embodied Water 55 L/kg6.6 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 scale38CrMoAlA

38CrMoAlA-CD vs 38CrMoAlA Q&T — frequently asked

Is 38CrMoAlA Q&T stronger than 38CrMoAlA-CD?

Yes. 38CrMoAlA Q&T has a typical yield strength of 880 MPa (128 ksi) against 700 MPa (102 ksi) for 38CrMoAlA-CD — about 26% more. Tensile strength is 1,030 MPa (149 ksi) vs 850 MPa (123 ksi).

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

Q&T is the default 38CrMoAlA 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, 38CrMoAlA-CD or 38CrMoAlA Q&T?

38CrMoAlA-CD, by a small margin. Both rate fair for machinability — 50/100 against 45/100 for 38CrMoAlA Q&T.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 38CrMoAlA-CD and 38CrMoAlA 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.