Steel A372 Gr E-A vs A372 Gr E CL70-QT
Steel · A372 Gr E temper comparison
A372 Gr E-A and A372 Gr E CL70-QT are two conditions of the same steel grade, A372 Gr E: A (solution annealed) versus CL70-QT (class 70). The chemistry is identical, so every difference below comes from the condition. A372 Gr E CL70-QT is the stronger of the two: yield strength 515 MPa (74.7 ksi) against 370 MPa (53.7 ksi) for A372 Gr E-A, about 39% more; tensile strength follows at 725 MPa (105 ksi) vs 590 MPa (85.6 ksi). In exchange, A372 Gr E-A is the more ductile: elongation 26% versus 20% for A372 Gr E CL70-QT, and A372 Gr E CL70-QT is harder (217 HB vs 170 HB). On the shop floor, A372 Gr E-A machines more easily (65 vs 55 out of 100) and A372 Gr E-A welds better (good vs fair).
A372 Gr E-AChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
A372 Gr E CL70-QTChoose it when strength drives the design.
A372 Gr E-A vs A372 Gr E CL70-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
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 520 MPa75.4 ksi · Shear Strength 435 MPa63.1 ksi · Fatigue Strength (Endurance Limit) 340 MPa49.3 ksi · Fracture Toughness (K_IC) 100 MPa·√m91 ksi·√in · Hardness, Rockwell C 20 HRC · Hardness, Vickers 228 HV
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.
Same in both: Thermal Conductivity 42 W/m·K24.3 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.3 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -30°C-22 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 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) -0.62 V · Corrosion Resistance 13 / 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 45 / 100 · Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 34 MJ/kg14,617 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.
A372 Gr E-A vs A372 Gr E CL70-QT — frequently asked
Is A372 Gr E CL70-QT stronger than A372 Gr E-A?
Yes. A372 Gr E CL70-QT has a typical yield strength of 515 MPa (74.7 ksi) against 370 MPa (53.7 ksi) for A372 Gr E-A — about 39% more. Tensile strength is 725 MPa (105 ksi) vs 590 MPa (85.6 ksi).
Which condition does FabDigit quote by default, A or CL70-QT?
CL70-QT is the default A372 Gr E 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, A372 Gr E-A or A372 Gr E CL70-QT?
A372 Gr E-A, by a small margin. Both rate good for machinability — 65/100 against 55/100 for A372 Gr E CL70-QT; for welding the order is A372 Gr E-A first (good, 55/100) then A372 Gr E CL70-QT (fair, 45/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in A372 Gr E-A and A372 Gr E CL70-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.