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Steel A514 Grade B-QT vs A514 Grade B QT-SR

Steel · A514 Grade B temper comparison

A514 Grade B-QT and A514 Grade B QT-SR are two conditions of the same steel grade, A514 Grade B: QT (quenched and tempered) versus QT-SR (Q&T + stress relieved). The chemistry is identical, so every difference below comes from the condition. A514 Grade B-QT is the stronger of the two: yield strength 760 MPa (110 ksi) against 720 MPa (104 ksi) for A514 Grade B QT-SR, about 6% more. A514 Grade B-QT is harder — 255 HB against 240 HB for A514 Grade B QT-SR — which matters for wear surfaces and threads.

A514 Grade B-QTChoose it when strength drives the design, or when surface hardness matters.

A514 Grade B-QT vs A514 Grade B QT-SR: properties

A514 Grade B-QTA514 Grade B QT-SR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

820 MPa119 ksi
790 MPa115 ksi

Yield Strength (0.2% offset)

760 MPa110 ksi
720 MPa104 ksi

Elongation at Break

19%
20%

Reduction in Area

50%
52%

Compressive Strength

760 MPa110 ksi
720 MPa104 ksi

Shear Strength

490 MPa71.1 ksi
475 MPa68.9 ksi

Fatigue Strength (Endurance Limit)

380 MPa55.1 ksi
365 MPa52.9 ksi

Fracture Toughness (K_IC)

140 MPa·√m127 ksi·√in
145 MPa·√m132 ksi·√in

Charpy V-Notch Impact (RT)

70 J51.6 ft·lbf
65 J47.9 ft·lbf

Hardness, Brinell

255 HB
240 HB

Hardness, Rockwell C

25 HRC
23 HRC

Hardness, Vickers

270 HV
252 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
425°C797 °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) 11.7 µm/m·K6.5 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -50°C-58 °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 15 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

35 / 100
38 / 100

Machinability Rating (AISI 1212 = 100 %)

30%
33%

Weldability

60 / 100
63 / 100

Formability (cold)

35 / 100
38 / 100

Same in both: Brazeability / Solderability 40 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 31 MJ/kg13,328 BTU/lb · Embodied Carbon (primary production) 2.3 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 scaleA514 Grade B

A514 Grade B-QT vs A514 Grade B QT-SR — frequently asked

Is A514 Grade B-QT stronger than A514 Grade B QT-SR?

Yes. A514 Grade B-QT has a typical yield strength of 760 MPa (110 ksi) against 720 MPa (104 ksi) for A514 Grade B QT-SR — about 6% more. Tensile strength is 820 MPa (119 ksi) vs 790 MPa (115 ksi).

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

QT is the default A514 Grade B 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.

When should I choose A514 Grade B-QT over A514 Grade B QT-SR?

Pick A514 Grade B-QT when strength drives the design, or when surface hardness matters.

Ready to make it?

Upload a CAD file and FabDigit prices the part in A514 Grade B-QT and A514 Grade B QT-SR 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.