Steel 4626-CD vs 4626 QT-38-42HRC
Steel · 4626 temper comparison
4626-CD and 4626 QT-38-42HRC are two conditions of the same steel grade, 4626: CD (cold drawn) versus QT-38-42HRC. The chemistry is identical, so every difference below comes from the condition. 4626 QT-38-42HRC is the stronger of the two: yield strength 1,180 MPa (171 ksi) against 580 MPa (84.1 ksi) for 4626-CD, about 103% more; tensile strength follows at 1,300 MPa (189 ksi) vs 680 MPa (98.6 ksi). In exchange, 4626-CD is the more ductile: elongation 15% versus 13% for 4626 QT-38-42HRC, and 4626 QT-38-42HRC is harder (375 HB vs 201 HB). 4626-CD runs hotter in service (350°C vs 300°C continuous). On the shop floor, 4626-CD welds better (fair vs poor).
4626-CDChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
4626 QT-38-42HRCChoose it when strength drives the design.
4626-CD vs 4626 QT-38-42HRC: 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 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 1,500°C2,732 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 44 W/m·K25.4 BTU/hr·ft·°F · Specific Heat Capacity 475 J/kg·K0.11 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 · Min Service Temperature -60°C-76 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 7.8 % IACS · Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 12 / 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 60 / 100 · Polishability 65 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 32 MJ/kg13,758 BTU/lb · Embodied Carbon (primary production) 2.3 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb · Typical Recycled Content 25%
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.
4626-CD vs 4626 QT-38-42HRC — frequently asked
Is 4626 QT-38-42HRC stronger than 4626-CD?
Yes. 4626 QT-38-42HRC has a typical yield strength of 1,180 MPa (171 ksi) against 580 MPa (84.1 ksi) for 4626-CD — about 103% more. Tensile strength is 1,300 MPa (189 ksi) vs 680 MPa (98.6 ksi).
Which condition does FabDigit quote by default, CD or QT-38-42HRC?
A is the default 4626 condition in the FabDigit quote flow (neither CD nor QT-38-42HRC). 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, 4626-CD or 4626 QT-38-42HRC?
4626-CD, by a small margin. Both rate good for machinability — 66/100 against 60/100 for 4626 QT-38-42HRC; for welding the order is 4626-CD first (fair, 43/100) then 4626 QT-38-42HRC (poor, 22/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 4626-CD and 4626 QT-38-42HRC 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.