Steel C45E Hot Rolled vs C45E-QT
Steel · C45E temper comparison
C45E Hot Rolled and C45E-QT are two conditions of the same steel grade, C45E: Hot Rolled versus QT (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. C45E-QT is the stronger of the two: yield strength 520 MPa (75.4 ksi) against 340 MPa (49.3 ksi) for C45E Hot Rolled, about 53% more; tensile strength follows at 760 MPa (110 ksi) vs 620 MPa (89.9 ksi). C45E-QT is harder — 225 HB against 180 HB for C45E Hot Rolled — which matters for wear surfaces and threads. C45E Hot Rolled runs hotter in service (350°C vs 300°C continuous). On the shop floor, C45E Hot Rolled welds better (48 vs 35 out of 100).
C45E Hot RolledChoose it when the part sees heat, or when it will be welded.
C45E-QTChoose it when strength drives the design, or when surface hardness matters.
C45E Hot Rolled vs C45E-QT: 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)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 210 GPa30.5 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) 1,420°C2,588 °F · Liquidus Temperature 1,495°C2,723 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 475 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.5 µm/m·K6.4 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 10 % IACS · Electrical Resistivity 1.7×10⁻⁷ Ω·m6.69 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 10 / 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 60 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 24 MJ/kg10,318 BTU/lb · Embodied Carbon (primary production) 2 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.
C45E Hot Rolled vs C45E-QT — frequently asked
Is C45E-QT stronger than C45E Hot Rolled?
Yes. C45E-QT has a typical yield strength of 520 MPa (75.4 ksi) against 340 MPa (49.3 ksi) for C45E Hot Rolled — about 53% more. Tensile strength is 760 MPa (110 ksi) vs 620 MPa (89.9 ksi).
Which condition does FabDigit quote by default, Hot Rolled or QT?
Normalized is the default C45E condition in the FabDigit quote flow (neither Hot Rolled nor QT). 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 welds better, C45E Hot Rolled or C45E-QT?
C45E Hot Rolled. Its weldability rates fair (48/100) against fair (35/100) for C45E-QT.
Ready to make it?
Upload a CAD file and FabDigit prices the part in C45E Hot Rolled and C45E-QT 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.