Steel O7-ANN vs O7 CD-ANN
Steel · O7 temper comparison
O7-ANN and O7 CD-ANN are two conditions of the same steel grade, O7: ANN (annealed) versus CD-ANN (cold drawn / precision ground annealed bar). The chemistry is identical, so every difference below comes from the condition. O7 CD-ANN is the stronger of the two: yield strength 520 MPa (75.4 ksi) against 400 MPa (58 ksi) for O7-ANN, about 30% more; tensile strength follows at 760 MPa (110 ksi) vs 690 MPa (100 ksi). In exchange, O7-ANN is the more ductile: elongation 24% versus 15% for O7 CD-ANN, and O7 CD-ANN is harder (217 HB vs 202 HB).
O7-ANNChoose it when the part is bent, formed or impact-loaded.
O7 CD-ANNChoose it when strength drives the design.
O7-ANN vs O7 CD-ANN: 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
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
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 7.8 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,450°C2,642 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 33 W/m·K19.1 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 · Max Service Temperature (continuous) 200°C392 °F · Min Service Temperature -30°C-22 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 3 % IACS · Electrical Resistivity 5.5×10⁻⁷ Ω·m21.7 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 %)
Formability (cold)
Same in both: Weldability 15 / 100 · Castability 20 / 100 · Brazeability / Solderability 40 / 100 · Polishability 70 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 33 MJ/kg14,187 BTU/lb · Embodied Carbon (primary production) 2.4 kg CO₂/kg · Embodied Water 65 L/kg7.8 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.
O7-ANN vs O7 CD-ANN — frequently asked
Is O7 CD-ANN stronger than O7-ANN?
Yes. O7 CD-ANN has a typical yield strength of 520 MPa (75.4 ksi) against 400 MPa (58 ksi) for O7-ANN — about 30% more. Tensile strength is 760 MPa (110 ksi) vs 690 MPa (100 ksi).
Which condition does FabDigit quote by default, ANN or CD-ANN?
ANN is the default O7 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.
When should I choose O7-ANN over O7 CD-ANN?
Pick O7-ANN when the part is bent, formed or impact-loaded. Pick O7 CD-ANN when strength drives the design.
Ready to make it?
Upload a CAD file and FabDigit prices the part in O7-ANN and O7 CD-ANN 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.