Steel P1-ANN vs P1-HOB
Steel · P1 temper comparison
P1-ANN and P1-HOB are two conditions of the same steel grade, P1: ANN (annealed) versus HOB (cold hobbed). The chemistry is identical, so every difference below comes from the condition. P1-HOB is the stronger of the two: yield strength 520 MPa (75.4 ksi) against 240 MPa (34.8 ksi) for P1-ANN, about 117% more; tensile strength follows at 620 MPa (89.9 ksi) vs 380 MPa (55.1 ksi). In exchange, P1-ANN is the more ductile: elongation 35% versus 10% for P1-HOB, and P1-HOB is harder (190 HB vs 120 HB). P1-ANN runs hotter in service (350°C vs 300°C continuous).
P1-ANNChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
P1-HOBChoose it when strength drives the design.
P1-ANN vs P1-HOB: 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)
Fracture Toughness (K_IC)
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 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,510°C2,750 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 11 % IACS · Electrical Resistivity 1.6×10⁻⁷ Ω·m6.3 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 10 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Castability 40 / 100 · Brazeability / Solderability 75 / 100 · Polishability 55 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 1.9 kg CO₂/kg · Embodied Water 45 L/kg5.4 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.
P1-ANN vs P1-HOB — frequently asked
Is P1-HOB stronger than P1-ANN?
Yes. P1-HOB has a typical yield strength of 520 MPa (75.4 ksi) against 240 MPa (34.8 ksi) for P1-ANN — about 117% more. Tensile strength is 620 MPa (89.9 ksi) vs 380 MPa (55.1 ksi).
Which condition does FabDigit quote by default, ANN or HOB?
ANN is the default P1 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, P1-ANN or P1-HOB?
P1-ANN, by a small margin. Both rate good for machinability — 60/100 against 55/100 for P1-HOB; for welding the order is P1-ANN first (excellent, 85/100) then P1-HOB (very good, 80/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in P1-ANN and P1-HOB 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.