Steel SUM41-A vs SUM41-CD
Steel · SUM41 temper comparison
SUM41-A and SUM41-CD are two conditions of the same steel grade, SUM41: A (solution annealed) versus CD (cold drawn). The chemistry is identical, so every difference below comes from the condition. SUM41-CD is the stronger of the two: yield strength 565 MPa (81.9 ksi) against 345 MPa (50 ksi) for SUM41-A, about 64% more; tensile strength follows at 655 MPa (95 ksi) vs 585 MPa (84.8 ksi). In exchange, SUM41-A is the more ductile: elongation 27% versus 10% for SUM41-CD, and SUM41-CD is harder (197 HB vs 174 HB).
SUM41-AChoose it when the part is bent, formed or impact-loaded.
SUM41-CDChoose it when strength drives the design.
SUM41-A vs SUM41-CD: 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
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
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 · Compressive Strength 570 MPa82.7 ksi · Shear Strength 425 MPa61.6 ksi · Fracture Toughness (K_IC) 55 MPa·√m50.1 ksi·√in · Hardness, Vickers 207 HV
Physical
Density and transition temperatures.
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,495°C2,723 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 49 W/m·K28.3 BTU/hr·ft·°F · Specific Heat Capacity 486 J/kg·K0.12 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.9 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 350°C662 °F · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 9.6 % IACS · Electrical Resistivity 1.8×10⁻⁷ Ω·m7.09 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 9 / 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 25 / 100 · Brazeability / Solderability 55 / 100 · Polishability 40 / 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.
SUM41-A vs SUM41-CD — frequently asked
Is SUM41-CD stronger than SUM41-A?
Yes. SUM41-CD has a typical yield strength of 565 MPa (81.9 ksi) against 345 MPa (50 ksi) for SUM41-A — about 64% more. Tensile strength is 655 MPa (95 ksi) vs 585 MPa (84.8 ksi).
Which condition does FabDigit quote by default, A or CD?
CD is the default SUM41 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 SUM41-A over SUM41-CD?
Pick SUM41-A when the part is bent, formed or impact-loaded. Pick SUM41-CD when strength drives the design.
Ready to make it?
Upload a CAD file and FabDigit prices the part in SUM41-A and SUM41-CD 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.