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Steel D4-ANN vs D4 HT+CRYO

Steel · D4 temper comparison

D4-ANN and D4 HT+CRYO are two conditions of the same steel grade, D4: ANN (annealed) versus HT+CRYO (hardened + deep cryogenic (-80 to -196 °C) + double temper, 61–63 HRC). The chemistry is identical, so every difference below comes from the condition. D4 HT+CRYO is the stronger of the two: yield strength 1,900 MPa (276 ksi) against 450 MPa (65.3 ksi) for D4-ANN, about 4.2 times as much; tensile strength follows at 2,050 MPa (297 ksi) vs 780 MPa (113 ksi). In exchange, D4-ANN is the more ductile: elongation 12% versus 0.8% for D4 HT+CRYO, and D4 HT+CRYO is harder (775 HV vs 247 HV). D4-ANN runs hotter in service (250°C vs 180°C continuous). On the shop floor, D4-ANN machines more easily (poor vs not recommended).

D4-ANNChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

D4 HT+CRYOChoose it when strength drives the design.

D4-ANN vs D4 HT+CRYO: properties

D4-ANND4 HT+CRYO

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

780 MPa113 ksi
2,050 MPa297 ksi

Yield Strength (0.2% offset)

450 MPa65.3 ksi
1,900 MPa276 ksi

Elongation at Break

12%
0.8%

Reduction in Area

20%
1%

Compressive Strength

900 MPa131 ksi
3,000 MPa435 ksi

Shear Strength

470 MPa68.2 ksi
1,240 MPa180 ksi

Fatigue Strength (Endurance Limit)

340 MPa49.3 ksi
820 MPa119 ksi

Fracture Toughness (K_IC)

22 MPa·√m20 ksi·√in
14 MPa·√m12.7 ksi·√in

Charpy V-Notch Impact (RT)

12 J8.9 ft·lbf
4 J3 ft·lbf

Hardness, Vickers

247 HV
775 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 0.28 · Hardness, Brinell 235 HB · Hardness, Rockwell B 99 HRB

Physical

Density and transition temperatures.

Same in both: Density 7.7 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,240°C2,264 °F · Liquidus Temperature 1,400°C2,552 °F

Thermal

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

Thermal Conductivity

20 W/m·K11.6 BTU/hr·ft·°F
19 W/m·K11 BTU/hr·ft·°F

Max Service Temperature (continuous)

250°C482 °F
180°C356 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11 µm/m·K6.1 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.7 % IACS
2.5 % IACS

Electrical Resistivity

6.5×10⁻⁷ Ω·m25.6 µΩ·in
6.9×10⁻⁷ Ω·m27.2 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

28 / 100
33 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.45 V

Manufacturability

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

Machinability

28 / 100
4 / 100

Machinability Rating (AISI 1212 = 100 %)

22%
3%

Weldability

12 / 100
4 / 100

Formability (cold)

8 / 100
1 / 100

Same in both: Castability 25 / 100 · Brazeability / Solderability 30 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 36 MJ/kg15,477 BTU/lb · Embodied Carbon (primary production) 2.6 kg CO₂/kg · Embodied Water 75 L/kg9 gal/lb · Typical Recycled Content 35%

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 scaleD4

D4-ANN vs D4 HT+CRYO — frequently asked

Is D4 HT+CRYO stronger than D4-ANN?

Yes. D4 HT+CRYO has a typical yield strength of 1,900 MPa (276 ksi) against 450 MPa (65.3 ksi) for D4-ANN — about 4.2 times as much. Tensile strength is 2,050 MPa (297 ksi) vs 780 MPa (113 ksi).

Which condition does FabDigit quote by default, ANN or HT+CRYO?

ANN is the default D4 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, D4-ANN or D4 HT+CRYO?

D4-ANN. Its machinability rates poor (28/100) against not recommended (4/100) for D4 HT+CRYO; for welding the order is D4-ANN first (not recommended, 12/100) then D4 HT+CRYO (not recommended, 4/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in D4-ANN and D4 HT+CRYO 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.