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Steel P500QL2-QT vs P500QL2 QT+SR

Steel · P500QL2 temper comparison

P500QL2-QT and P500QL2 QT+SR are two conditions of the same steel grade, P500QL2: QT (quenched and tempered) versus QT+SR (Q+T + stress relieved / simulated PWHT). The chemistry is identical, so every difference below comes from the condition. Both yield at about 545 MPa — the mechanical properties are the same, and the difference is in how the stock is processed and what it is certified to (quenched and tempered versus Q+T + stress relieved / simulated PWHT). P500QL2-QT is harder — 19 HRC against 15 HRC for P500QL2 QT+SR — which matters for wear surfaces and threads.

P500QL2-QTChoose it when surface hardness matters.

P500QL2-QT vs P500QL2 QT+SR: properties

P500QL2-QTP500QL2 QT+SR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

660 MPa95.7 ksi
630 MPa91.4 ksi

Yield Strength (0.2% offset)

545 MPa79 ksi
520 MPa75.4 ksi

Elongation at Break

21%
22%

Reduction in Area

60%
62%

Compressive Strength

545 MPa79 ksi
520 MPa75.4 ksi

Shear Strength

400 MPa58 ksi
385 MPa55.8 ksi

Fatigue Strength (Endurance Limit)

300 MPa43.5 ksi
285 MPa41.3 ksi

Fracture Toughness (K_IC)

130 MPa·√m118 ksi·√in
140 MPa·√m127 ksi·√in

Charpy V-Notch Impact (RT)

140 J103 ft·lbf
130 J95.9 ft·lbf

Hardness, Brinell

215 HB
205 HB

Hardness, Rockwell B

95 HRB
94 HRB

Hardness, Rockwell C

19 HRC
15 HRC

Hardness, Vickers

225 HV
215 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 0.29

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 1,500°C2,732 °F

Thermal

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

Same in both: Thermal Conductivity 38 W/m·K22 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 -60°C-76 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 7.2 % IACS · Electrical Resistivity 2.4×10⁻⁷ Ω·m9.45 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

45 / 100
48 / 100

Machinability Rating (AISI 1212 = 100 %)

55%
58%

Weldability

60 / 100
62 / 100

Formability (cold)

40 / 100
43 / 100

Same in both: 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 20%

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 scaleP500QL2

P500QL2-QT vs P500QL2 QT+SR — frequently asked

What is the difference between P500QL2-QT and P500QL2 QT+SR?

P500QL2-QT and P500QL2 QT+SR are two conditions of the same steel grade, P500QL2: QT (quenched and tempered) versus QT+SR (Q+T + stress relieved / simulated PWHT). The chemistry is identical, so every difference below comes from the condition. Both yield at about 545 MPa — the mechanical properties are the same, and the difference is in how the stock is processed and what it is certified to (quenched and tempered versus Q+T + stress relieved / simulated PWHT).

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

QT is the default P500QL2 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 P500QL2-QT over P500QL2 QT+SR?

Pick P500QL2-QT when surface hardness matters.

Ready to make it?

Upload a CAD file and FabDigit prices the part in P500QL2-QT and P500QL2 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.