Steel A653-HR vs A653-SS40
Steel · A653 temper comparison
A653-HR and A653-SS40 are two conditions of the same steel grade, A653: HR (hot rolled) versus SS40 (SS Grade 40 [275]). The chemistry is identical, so every difference below comes from the condition. A653-SS40 is the stronger of the two: yield strength 305 MPa (44.2 ksi) against 260 MPa (37.7 ksi) for A653-HR, about 17% more; tensile strength follows at 400 MPa (58 ksi) vs 360 MPa (52.2 ksi). In exchange, A653-HR is the more ductile: elongation 32% versus 22% for A653-SS40, and A653-SS40 is harder (118 HB vs 110 HB).
A653-HRChoose it when the part is bent, formed or impact-loaded.
A653-SS40Choose it when strength drives the design.
A653-HR vs A653-SS40: 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 200 GPa29 Msi · Shear Modulus 79 GPa11.5 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) 1,495°C2,723 °F · Liquidus Temperature 1,520°C2,768 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
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 · Max Service Temperature (continuous) 200°C392 °F · Min Service Temperature -30°C-22 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -1.02 V · Corrosion Resistance 38 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Formability (cold)
Same in both: Machinability Rating (AISI 1212 = 100 %) 66% · Weldability 72 / 100 · Brazeability / Solderability 70 / 100 · Polishability 25 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 30 MJ/kg12,898 BTU/lb · Embodied Carbon (primary production) 2.5 kg CO₂/kg · Embodied Water 60 L/kg7.2 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.
A653-HR vs A653-SS40 — frequently asked
Is A653-SS40 stronger than A653-HR?
Yes. A653-SS40 has a typical yield strength of 305 MPa (44.2 ksi) against 260 MPa (37.7 ksi) for A653-HR — about 17% more. Tensile strength is 400 MPa (58 ksi) vs 360 MPa (52.2 ksi).
Which condition does FabDigit quote by default, HR or SS40?
HR is the default A653 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 A653-HR over A653-SS40?
Pick A653-HR when the part is bent, formed or impact-loaded. Pick A653-SS40 when strength drives the design.
Ready to make it?
Upload a CAD file and FabDigit prices the part in A653-HR and A653-SS40 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.