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Steel A372 Gr E-A vs A372 Gr E CL65-QT

Steel · A372 Gr E temper comparison

A372 Gr E-A and A372 Gr E CL65-QT are two conditions of the same steel grade, A372 Gr E: A (solution annealed) versus CL65-QT (class 65). The chemistry is identical, so every difference below comes from the condition. A372 Gr E CL65-QT is the stronger of the two: yield strength 485 MPa (70.3 ksi) against 370 MPa (53.7 ksi) for A372 Gr E-A, about 31% more; tensile strength follows at 700 MPa (102 ksi) vs 590 MPa (85.6 ksi). In exchange, A372 Gr E-A is the more ductile: elongation 26% versus 22% for A372 Gr E CL65-QT, and A372 Gr E CL65-QT is harder (207 HB vs 170 HB).

A372 Gr E-AChoose it when the part is bent, formed or impact-loaded.

A372 Gr E CL65-QTChoose it when strength drives the design.

A372 Gr E-A vs A372 Gr E CL65-QT: properties

A372 Gr E-AA372 Gr E CL65-QT

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

590 MPa85.6 ksi
700 MPa102 ksi

Yield Strength (0.2% offset)

370 MPa53.7 ksi
485 MPa70.3 ksi

Elongation at Break

26%
22%

Reduction in Area

58%
52%

Compressive Strength

520 MPa75.4 ksi
490 MPa71.1 ksi

Shear Strength

435 MPa63.1 ksi
420 MPa60.9 ksi

Fatigue Strength (Endurance Limit)

340 MPa49.3 ksi
325 MPa47.1 ksi

Fracture Toughness (K_IC)

100 MPa·√m91 ksi·√in
105 MPa·√m95.6 ksi·√in

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
62 J45.7 ft·lbf

Hardness, Brinell

170 HB
207 HB

Hardness, Rockwell B

87 HRB
96 HRB

Hardness, Rockwell C

20 HRC
18 HRC

Hardness, Vickers

228 HV
217 HV

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)

400°C752 °F
410°C770 °F

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 · 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

65 / 100
58 / 100

Machinability Rating (AISI 1212 = 100 %)

68%
60%

Weldability

55 / 100
47 / 100

Formability (cold)

40 / 100
30 / 100

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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scaleA372 Gr E

A372 Gr E-A vs A372 Gr E CL65-QT — frequently asked

Is A372 Gr E CL65-QT stronger than A372 Gr E-A?

Yes. A372 Gr E CL65-QT has a typical yield strength of 485 MPa (70.3 ksi) against 370 MPa (53.7 ksi) for A372 Gr E-A — about 31% more. Tensile strength is 700 MPa (102 ksi) vs 590 MPa (85.6 ksi).

Which condition does FabDigit quote by default, A or CL65-QT?

CL70-QT is the default A372 Gr E condition in the FabDigit quote flow (neither A nor CL65-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 is easier to machine, A372 Gr E-A or A372 Gr E CL65-QT?

A372 Gr E-A, by a small margin. Both rate good for machinability — 65/100 against 58/100 for A372 Gr E CL65-QT; for welding the order is A372 Gr E-A first (good, 55/100) then A372 Gr E CL65-QT (fair, 47/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in A372 Gr E-A and A372 Gr E CL65-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.