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Steel P690QL1-QT vs P690QL1 QT-50-100

Steel · P690QL1 temper comparison

P690QL1-QT and P690QL1 QT-50-100 are two conditions of the same steel grade, P690QL1: QT (quenched and tempered) versus QT-50-100 (QT). The chemistry is identical, so every difference below comes from the condition. P690QL1-QT is the stronger of the two: yield strength 730 MPa (106 ksi) against 690 MPa (100 ksi) for P690QL1 QT-50-100, about 6% more. P690QL1-QT is harder — 26 HRC against 24 HRC for P690QL1 QT-50-100 — which matters for wear surfaces and threads.

P690QL1-QTChoose it when strength drives the design, or when surface hardness matters.

P690QL1-QT vs P690QL1 QT-50-100: properties

P690QL1-QTP690QL1 QT-50-100

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

830 MPa120 ksi
800 MPa116 ksi

Yield Strength (0.2% offset)

730 MPa106 ksi
690 MPa100 ksi

Compressive Strength

730 MPa106 ksi
690 MPa100 ksi

Shear Strength

500 MPa72.5 ksi
480 MPa69.6 ksi

Fatigue Strength (Endurance Limit)

380 MPa55.1 ksi
360 MPa52.2 ksi

Fracture Toughness (K_IC)

130 MPa·√m118 ksi·√in
125 MPa·√m114 ksi·√in

Charpy V-Notch Impact (RT)

120 J88.5 ft·lbf
100 J73.8 ft·lbf

Hardness, Brinell

260 HB
250 HB

Hardness, Rockwell C

26 HRC
24 HRC

Hardness, Vickers

273 HV
263 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 165 GPa23.9 Msi · Poisson's Ratio 0.3 · Elongation at Break 17% · Reduction in Area 55%

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,440°C2,624 °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 36 W/m·K20.8 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 6.9 % IACS · Electrical Resistivity 2.5×10⁻⁷ Ω·m9.84 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

40 / 100
42 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
47%

Formability (cold)

45 / 100
43 / 100

Same in both: Weldability 65 / 100 · Brazeability / Solderability 40 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 30 MJ/kg12,898 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 scaleP690QL1

P690QL1-QT vs P690QL1 QT-50-100 — frequently asked

Is P690QL1-QT stronger than P690QL1 QT-50-100?

Yes. P690QL1-QT has a typical yield strength of 730 MPa (106 ksi) against 690 MPa (100 ksi) for P690QL1 QT-50-100 — about 6% more. Tensile strength is 830 MPa (120 ksi) vs 800 MPa (116 ksi).

Which condition does FabDigit quote by default, QT or QT-50-100?

QT is the default P690QL1 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 P690QL1-QT over P690QL1 QT-50-100?

Pick P690QL1-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 P690QL1-QT and P690QL1 QT-50-100 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.