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Steel S1100QL-QT vs S1100QL QT+SR

Steel · S1100QL temper comparison

S1100QL-QT and S1100QL QT+SR are two conditions of the same steel grade, S1100QL: QT (quenched and tempered) versus QT+SR (QT + stress relieved). The chemistry is identical, so every difference below comes from the condition. Both yield at about 1,150 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 QT + stress relieved). For most parts the choice follows the drawing's specified condition; ask for the one your standard calls out.

S1100QL-QT vs S1100QL QT+SR: properties

S1100QL-QTS1100QL QT+SR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

1,350 MPa196 ksi
1,300 MPa189 ksi

Yield Strength (0.2% offset)

1,150 MPa167 ksi
1,100 MPa160 ksi

Elongation at Break

10%
11%

Reduction in Area

45%
47%

Compressive Strength

1,150 MPa167 ksi
1,100 MPa160 ksi

Shear Strength

800 MPa116 ksi
770 MPa112 ksi

Fatigue Strength (Endurance Limit)

560 MPa81.2 ksi
550 MPa79.8 ksi

Fracture Toughness (K_IC)

75 MPa·√m68.3 ksi·√in
80 MPa·√m72.8 ksi·√in

Hardness, Brinell

400 HB
385 HB

Hardness, Rockwell C

42 HRC
40 HRC

Hardness, Vickers

420 HV
400 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 · Charpy V-Notch Impact (RT) 60 J44.3 ft·lbf

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 32 W/m·K18.5 BTU/hr·ft·°F · Specific Heat Capacity 470 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) 250°C482 °F · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 7.5 % IACS · Electrical Resistivity 2.3×10⁻⁷ Ω·m9.06 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

30 / 100
32 / 100

Machinability Rating (AISI 1212 = 100 %)

35%
37%

Weldability

55 / 100
58 / 100

Formability (cold)

30 / 100
32 / 100

Same in both: 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 scaleS1100QL

S1100QL-QT vs S1100QL QT+SR — frequently asked

What is the difference between S1100QL-QT and S1100QL QT+SR?

S1100QL-QT and S1100QL QT+SR are two conditions of the same steel grade, S1100QL: QT (quenched and tempered) versus QT+SR (QT + stress relieved). The chemistry is identical, so every difference below comes from the condition. Both yield at about 1,150 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 QT + stress relieved).

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

QT is the default S1100QL 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.

Ready to make it?

Upload a CAD file and FabDigit prices the part in S1100QL-QT and S1100QL 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.