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Steel P355QL1-QT vs P355QL1 QT-100-150

Steel · P355QL1 temper comparison

P355QL1-QT and P355QL1 QT-100-150 are two conditions of the same steel grade, P355QL1: QT (quenched and tempered) versus QT-100-150 (QT). The chemistry is identical, so every difference below comes from the condition. P355QL1-QT is the stronger of the two: yield strength 400 MPa (58 ksi) against 360 MPa (52.2 ksi) for P355QL1 QT-100-150, about 11% more; tensile strength follows at 560 MPa (81.2 ksi) vs 520 MPa (75.4 ksi). P355QL1-QT is harder — 175 HB against 165 HB for P355QL1 QT-100-150 — which matters for wear surfaces and threads.

P355QL1-QTChoose it when strength drives the design, or when surface hardness matters.

P355QL1-QT vs P355QL1 QT-100-150: properties

P355QL1-QTP355QL1 QT-100-150

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

560 MPa81.2 ksi
520 MPa75.4 ksi

Yield Strength (0.2% offset)

400 MPa58 ksi
360 MPa52.2 ksi

Elongation at Break

26%
24%

Reduction in Area

60%
56%

Compressive Strength

400 MPa58 ksi
360 MPa52.2 ksi

Shear Strength

340 MPa49.3 ksi
315 MPa45.7 ksi

Fatigue Strength (Endurance Limit)

255 MPa37 ksi
235 MPa34.1 ksi

Fracture Toughness (K_IC)

130 MPa·√m118 ksi·√in
120 MPa·√m109 ksi·√in

Charpy V-Notch Impact (RT)

150 J111 ft·lbf
110 J81.1 ft·lbf

Hardness, Brinell

175 HB
165 HB

Hardness, Rockwell B

88 HRB
84 HRB

Hardness, Vickers

185 HV
175 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.3

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,460°C2,660 °F · Liquidus Temperature 1,510°C2,750 °F

Thermal

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

Same in both: Thermal Conductivity 44 W/m·K25.4 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 7.8 % 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 12 / 100

Manufacturability

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

Machinability

55 / 100
57 / 100

Machinability Rating (AISI 1212 = 100 %)

62%
65%

Weldability

80 / 100
78 / 100

Formability (cold)

60 / 100
56 / 100

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

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 26 MJ/kg11,178 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Embodied Water 45 L/kg5.4 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 scaleP355QL1

P355QL1-QT vs P355QL1 QT-100-150 — frequently asked

Is P355QL1-QT stronger than P355QL1 QT-100-150?

Yes. P355QL1-QT has a typical yield strength of 400 MPa (58 ksi) against 360 MPa (52.2 ksi) for P355QL1 QT-100-150 — about 11% more. Tensile strength is 560 MPa (81.2 ksi) vs 520 MPa (75.4 ksi).

Which condition does FabDigit quote by default, QT or QT-100-150?

QT is the default P355QL1 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 P355QL1-QT over P355QL1 QT-100-150?

Pick P355QL1-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 P355QL1-QT and P355QL1 QT-100-150 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.