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Steel A372 Grade L-F vs A372 Grade L QT-40-44HRC

Steel · A372 Grade L temper comparison

A372 Grade L-F and A372 Grade L QT-40-44HRC are two conditions of the same steel grade, A372 Grade L: F (as fabricated) versus QT-40-44HRC. The chemistry is identical, so every difference below comes from the condition. A372 Grade L QT-40-44HRC is the stronger of the two: yield strength 1,170 MPa (170 ksi) against 500 MPa (72.5 ksi) for A372 Grade L-F, about 134% more; tensile strength follows at 1,310 MPa (190 ksi) vs 800 MPa (116 ksi). In exchange, A372 Grade L-F is the more ductile: elongation 18% versus 13% for A372 Grade L QT-40-44HRC, and A372 Grade L QT-40-44HRC is harder (401 HB vs 255 HB). On the shop floor, A372 Grade L-F welds better (32 vs 15 out of 100).

A372 Grade L-FChoose it when the part is bent, formed or impact-loaded, or when it will be welded.

A372 Grade L QT-40-44HRCChoose it when strength drives the design.

A372 Grade L-F vs A372 Grade L QT-40-44HRC: properties

A372 Grade L-FA372 Grade L QT-40-44HRC

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

800 MPa116 ksi
1,310 MPa190 ksi

Yield Strength (0.2% offset)

500 MPa72.5 ksi
1,170 MPa170 ksi

Elongation at Break

18%
13%

Compressive Strength

515 MPa74.7 ksi
1,050 MPa152 ksi

Shear Strength

480 MPa69.6 ksi
700 MPa102 ksi

Fatigue Strength (Endurance Limit)

360 MPa52.2 ksi
580 MPa84.1 ksi

Fracture Toughness (K_IC)

85 MPa·√m77.4 ksi·√in
55 MPa·√m50.1 ksi·√in

Charpy V-Notch Impact (RT)

28 J20.7 ft·lbf
20 J14.8 ft·lbf

Hardness, Brinell

255 HB
401 HB

Hardness, Rockwell C

25 HRC
42 HRC

Hardness, Vickers

268 HV
420 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 · Reduction in Area 40%

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,416°C2,581 °F · Liquidus Temperature 1,470°C2,678 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

44 W/m·K25.4 BTU/hr·ft·°F
42 W/m·K24.3 BTU/hr·ft·°F

Max Service Temperature (continuous)

370°C698 °F
400°C752 °F

Same in both: Specific Heat Capacity 473 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 -40°C-40 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

8.1 % IACS
7.8 % IACS

Electrical Resistivity

2.13×10⁻⁷ Ω·m8.39 µΩ·in
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

47 / 100
38 / 100

Machinability Rating (AISI 1212 = 100 %)

50%
30%

Weldability

32 / 100
15 / 100

Formability (cold)

22 / 100
12 / 100

Same in both: Brazeability / Solderability 45 / 100 · Polishability 68 / 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 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.

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

A372 Grade L-F vs A372 Grade L QT-40-44HRC — frequently asked

Is A372 Grade L QT-40-44HRC stronger than A372 Grade L-F?

Yes. A372 Grade L QT-40-44HRC has a typical yield strength of 1,170 MPa (170 ksi) against 500 MPa (72.5 ksi) for A372 Grade L-F — about 134% more. Tensile strength is 1,310 MPa (190 ksi) vs 800 MPa (116 ksi).

Which condition does FabDigit quote by default, F or QT-40-44HRC?

QT-HS is the default A372 Grade L condition in the FabDigit quote flow (neither F nor QT-40-44HRC). 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 Grade L-F or A372 Grade L QT-40-44HRC?

A372 Grade L-F, by a small margin. Both rate fair for machinability — 47/100 against 38/100 for A372 Grade L QT-40-44HRC; for welding the order is A372 Grade L-F first (poor, 32/100) then A372 Grade L QT-40-44HRC (poor, 15/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in A372 Grade L-F and A372 Grade L QT-40-44HRC 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.