FabDigitFabDigit

Steel A372 Grade C-N vs A372 Grade C-QT

Steel · A372 Grade C temper comparison

A372 Grade C-N and A372 Grade C-QT are two conditions of the same steel grade, A372 Grade C: N (normalized) versus QT (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. A372 Grade C-QT is the stronger of the two: yield strength 550 MPa (79.8 ksi) against 415 MPa (60.2 ksi) for A372 Grade C-N, about 33% more; tensile strength follows at 725 MPa (105 ksi) vs 655 MPa (95 ksi). A372 Grade C-QT is harder — 217 HB against 197 HB for A372 Grade C-N — which matters for wear surfaces and threads.

A372 Grade C-QTChoose it when strength drives the design, or when surface hardness matters.

A372 Grade C-N vs A372 Grade C-QT: properties

A372 Grade C-NA372 Grade C-QT

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

655 MPa95 ksi
725 MPa105 ksi

Yield Strength (0.2% offset)

415 MPa60.2 ksi
550 MPa79.8 ksi

Reduction in Area

42%
52%

Compressive Strength

415 MPa60.2 ksi
420 MPa60.9 ksi

Shear Strength

395 MPa57.3 ksi
380 MPa55.1 ksi

Fatigue Strength (Endurance Limit)

295 MPa42.8 ksi
330 MPa47.9 ksi

Fracture Toughness (K_IC)

60 MPa·√m54.6 ksi·√in
80 MPa·√m72.8 ksi·√in

Charpy V-Notch Impact (RT)

30 J22.1 ft·lbf
55 J40.6 ft·lbf

Hardness, Brinell

197 HB
217 HB

Hardness, Rockwell B

93 HRB
96 HRB

Hardness, Vickers

207 HV
196 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 · Elongation at Break 20%

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 1,490°C2,714 °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) 12.2 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 247 J/g106 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -29°C-20 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 9 % IACS · Electrical Resistivity 1.9×10⁻⁷ Ω·m7.48 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

52 / 100
55 / 100

Machinability Rating (AISI 1212 = 100 %)

55%
50%

Weldability

45 / 100
40 / 100

Formability (cold)

35 / 100
40 / 100

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) 2.1 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.

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

A372 Grade C-N vs A372 Grade C-QT — frequently asked

Is A372 Grade C-QT stronger than A372 Grade C-N?

Yes. A372 Grade C-QT has a typical yield strength of 550 MPa (79.8 ksi) against 415 MPa (60.2 ksi) for A372 Grade C-N — about 33% more. Tensile strength is 725 MPa (105 ksi) vs 655 MPa (95 ksi).

Which condition does FabDigit quote by default, N or QT?

N+T is the default A372 Grade C condition in the FabDigit quote flow (neither N 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, A372 Grade C-N or A372 Grade C-QT?

A372 Grade C-N. Its weldability rates fair (45/100) against fair (40/100) for A372 Grade C-QT.

Ready to make it?

Upload a CAD file and FabDigit prices the part in A372 Grade C-N and A372 Grade C-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.