Steel A4-ANN vs A4 HT-CRYO
Steel · A4 temper comparison
A4-ANN and A4 HT-CRYO are two conditions of the same steel grade, A4: ANN (annealed) versus HT-CRYO (hardened + deep cryogenic treatment + double temper). The chemistry is identical, so every difference below comes from the condition. A4 HT-CRYO is the stronger of the two: yield strength 1,800 MPa (261 ksi) against 415 MPa (60.2 ksi) for A4-ANN, about 4.3 times as much; tensile strength follows at 2,050 MPa (297 ksi) vs 745 MPa (108 ksi). In exchange, A4-ANN is the more ductile: elongation 20% versus 1.5% for A4 HT-CRYO, and A4 HT-CRYO is harder (715 HV vs 235 HV). A4-ANN runs hotter in service (400°C vs 175°C continuous). On the shop floor, A4-ANN machines more easily (good vs not recommended).
A4-ANNChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
A4 HT-CRYOChoose it when strength drives the design.
A4-ANN vs A4 HT-CRYO: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 203 GPa29.4 Msi · Shear Modulus 79 GPa11.5 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Reduction in Area 40% · Shear Strength 450 MPa65.3 ksi · Hardness, Brinell 225 HB · Hardness, Rockwell B 98 HRB
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 1,470°C2,678 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 25 W/m·K14.4 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.5 µm/m·K6.4 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -50°C-58 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 2.7 % IACS · Electrical Resistivity 6.4×10⁻⁷ Ω·m25.2 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
Machinability Rating (AISI 1212 = 100 %)
Same in both: Weldability 25 / 100 · Formability (cold) 30 / 100 · Castability 20 / 100 · Brazeability / Solderability 40 / 100 · Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 36 MJ/kg15,477 BTU/lb · Embodied Carbon (primary production) 2.8 kg CO₂/kg · Embodied Water 70 L/kg8.4 gal/lb · Typical Recycled Content 45%
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.
A4-ANN vs A4 HT-CRYO — frequently asked
Is A4 HT-CRYO stronger than A4-ANN?
Yes. A4 HT-CRYO has a typical yield strength of 1,800 MPa (261 ksi) against 415 MPa (60.2 ksi) for A4-ANN — about 4.3 times as much. Tensile strength is 2,050 MPa (297 ksi) vs 745 MPa (108 ksi).
Which condition does FabDigit quote by default, ANN or HT-CRYO?
ANN is the default A4 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, A4-ANN or A4 HT-CRYO?
A4-ANN. Its machinability rates good (55/100) against not recommended (5/100) for A4 HT-CRYO.
Ready to make it?
Upload a CAD file and FabDigit prices the part in A4-ANN and A4 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.