Steel SUM41-CD vs SUM41 QT-229HB
Steel · SUM41 temper comparison
SUM41-CD and SUM41 QT-229HB are two conditions of the same steel grade, SUM41: CD (cold drawn) versus QT-229HB (Q&T). The chemistry is identical, so every difference below comes from the condition. SUM41 QT-229HB is the stronger of the two: tensile strength 705 MPa (102 ksi) against 655 MPa (95 ksi) for SUM41-CD, about 8% more. SUM41 QT-229HB is the more ductile: elongation 24% versus 10% for SUM41-CD, and SUM41 QT-229HB is harder (229 HB vs 197 HB). On the shop floor, SUM41-CD machines more easily (very good vs good).
SUM41-CDChoose it when the part is machined in volume.
SUM41 QT-229HBChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
SUM41-CD vs SUM41 QT-229HB: 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)
Elongation at Break
Reduction in Area
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 · Yield Strength (0.2% offset) 565 MPa81.9 ksi · Compressive Strength 570 MPa82.7 ksi
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.
Thermal Conductivity
Same in both: 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.
Electrical Conductivity
Electrical Resistivity
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 %)
Weldability
Formability (cold)
Same in both: 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-CD vs SUM41 QT-229HB — frequently asked
Is SUM41 QT-229HB stronger than SUM41-CD?
Yes. SUM41 QT-229HB has a typical tensile strength of 705 MPa (102 ksi) against 655 MPa (95 ksi) for SUM41-CD — about 8% more.
Which condition does FabDigit quote by default, CD or QT-229HB?
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.
Which is easier to machine, SUM41-CD or SUM41 QT-229HB?
SUM41-CD. Its machinability rates very good (78/100) against good (68/100) for SUM41 QT-229HB; for welding the order is SUM41-CD first (poor, 25/100) then SUM41 QT-229HB (poor, 20/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in SUM41-CD and SUM41 QT-229HB 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.