Steel 08Al CR-SP vs 08Al-HR
Steel · 08Al temper comparison
08Al CR-SP and 08Al-HR are two conditions of the same steel grade, 08Al: CR-SP (CR Skin-Passed / Temper Rolled) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. 08Al-HR is the stronger of the two: yield strength 220 MPa (31.9 ksi) against 170 MPa (24.7 ksi) for 08Al CR-SP, about 29% more; tensile strength follows at 340 MPa (49.3 ksi) vs 310 MPa (45 ksi). In exchange, 08Al CR-SP is the more ductile: elongation 40% versus 35% for 08Al-HR, and 08Al-HR is harder (105 HB vs 95 HB).
08Al CR-SPChoose it when the part is bent, formed or impact-loaded.
08Al-HRChoose it when strength drives the design.
08Al CR-SP vs 08Al-HR: 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
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 207 GPa30 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 7.87 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,495°C2,723 °F · Liquidus Temperature 1,530°C2,786 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 60 W/m·K34.7 BTU/hr·ft·°F · Specific Heat Capacity 480 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 · Max Service Temperature (continuous) 350°C662 °F · Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 12 % IACS · Electrical Resistivity 1.45×10⁻⁷ Ω·m5.71 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V
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 95 / 100 · Brazeability / Solderability 70 / 100 · Polishability 50 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 2.1 kg CO₂/kg · Embodied Water 40 L/kg4.8 gal/lb · Typical Recycled Content 20%
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.
08Al CR-SP vs 08Al-HR — frequently asked
Is 08Al-HR stronger than 08Al CR-SP?
Yes. 08Al-HR has a typical yield strength of 220 MPa (31.9 ksi) against 170 MPa (24.7 ksi) for 08Al CR-SP — about 29% more. Tensile strength is 340 MPa (49.3 ksi) vs 310 MPa (45 ksi).
Which condition does FabDigit quote by default, CR-SP or HR?
CR-A is the default 08Al condition in the FabDigit quote flow (neither CR-SP nor HR). 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 08Al CR-SP over 08Al-HR?
Pick 08Al CR-SP when the part is bent, formed or impact-loaded. Pick 08Al-HR when strength drives the design.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 08Al CR-SP and 08Al-HR 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.