Steel E360-QT30 vs E360-QT45
Steel · E360 temper comparison
E360-QT30 and E360-QT45 are two conditions of the same steel grade, E360: QT30 (Q&T 28–34 HRC) versus QT45 (Q&T 42–48 HRC). The chemistry is identical, so every difference below comes from the condition. E360-QT45 is the stronger of the two: yield strength 1,150 MPa (167 ksi) against 700 MPa (102 ksi) for E360-QT30, about 64% more; tensile strength follows at 1,450 MPa (210 ksi) vs 950 MPa (138 ksi). In exchange, E360-QT30 is the more ductile: elongation 13% versus 6% for E360-QT45, and E360-QT30 is harder (295 HB vs 215 HB). On the shop floor, E360-QT30 machines more easily (32 vs 15 out of 100) and E360-QT30 welds better (poor vs not recommended).
E360-QT30Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
E360-QT45Choose it when strength drives the design.
E360-QT30 vs E360-QT45: 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)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Compressive Strength 380 MPa55.1 ksi · Shear Strength 440 MPa63.8 ksi · Hardness, Rockwell B 96 HRB
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 1,480°C2,696 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 48 W/m·K27.7 BTU/hr·ft·°F · 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 250 J/g107 BTU/lb · Max Service Temperature (continuous) 350°C662 °F · Min Service Temperature -10°C14 °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) -0.6 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 55 / 100 · Polishability 55 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Embodied Water 40 L/kg4.8 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.
E360-QT30 vs E360-QT45 — frequently asked
Is E360-QT45 stronger than E360-QT30?
Yes. E360-QT45 has a typical yield strength of 1,150 MPa (167 ksi) against 700 MPa (102 ksi) for E360-QT30 — about 64% more. Tensile strength is 1,450 MPa (210 ksi) vs 950 MPa (138 ksi).
Which condition does FabDigit quote by default, QT30 or QT45?
+AR is the default E360 condition in the FabDigit quote flow (neither QT30 nor QT45). 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, E360-QT30 or E360-QT45?
E360-QT30, by a small margin. Both rate poor for machinability — 32/100 against 15/100 for E360-QT45; for welding the order is E360-QT30 first (poor, 20/100) then E360-QT45 (not recommended, 10/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in E360-QT30 and E360-QT45 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.