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Stainless Steel 1.3549 +C vs 1.3549 QT 500 (54-57 HRC)

Stainless Steel · 1.3549 temper comparison

1.3549 +C and 1.3549 QT 500 (54-57 HRC) are two conditions of the same stainless steel grade, 1.3549: +C (cold drawn) versus QT 500 (54-57 HRC) (hardened + secondary-hardening temper 500–520 °C). The chemistry is identical, so every difference below comes from the condition. 1.3549 QT 500 (54-57 HRC) is the stronger of the two: yield strength 1,700 MPa (247 ksi) against 620 MPa (89.9 ksi) for 1.3549 +C, about 174% more; tensile strength follows at 1,850 MPa (268 ksi) vs 880 MPa (128 ksi). In exchange, 1.3549 +C is the more ductile: elongation 9% versus 2.5% for 1.3549 QT 500 (54-57 HRC), and 1.3549 +C is harder (275 HB vs 245 HB). 1.3549 QT 500 (54-57 HRC) runs hotter in service (400°C vs 250°C continuous). On the shop floor, 1.3549 +C machines more easily (poor vs not recommended).

1.3549 +CChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

1.3549 QT 500 (54-57 HRC)Choose it when strength drives the design, or when the part sees heat.

1.3549 +C vs 1.3549 QT 500 (54-57 HRC): properties

1.3549 +C1.3549 QT 500 (54-57 HRC)

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

880 MPa128 ksi
1,850 MPa268 ksi

Yield Strength (0.2% offset)

620 MPa89.9 ksi
1,700 MPa247 ksi

Elongation at Break

9%
2.5%

Reduction in Area

25%
35%

Compressive Strength

1,000 MPa145 ksi
900 MPa131 ksi

Shear Strength

540 MPa78.3 ksi
480 MPa69.6 ksi

Fatigue Strength (Endurance Limit)

400 MPa58 ksi
680 MPa98.6 ksi

Fracture Toughness (K_IC)

42 MPa·√m38.2 ksi·√in
45 MPa·√m41 ksi·√in

Charpy V-Notch Impact (RT)

14 J10.3 ft·lbf
6 J4.4 ft·lbf

Hardness, Brinell

275 HB
245 HB

Hardness, Rockwell C

28 HRC
56 HRC

Hardness, Vickers

290 HV
615 HV

Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 78 GPa11.3 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.28 · Hardness, Rockwell B 99 HRB

Physical

Density and transition temperatures.

Same in both: Density 7.7 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,370°C2,498 °F · Liquidus Temperature 1,420°C2,588 °F

Thermal

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

Max Service Temperature (continuous)

250°C482 °F
400°C752 °F

Same in both: Thermal Conductivity 24 W/m·K13.9 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 10.4 µm/m·K5.8 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -70°C-94 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 2.9 % IACS · Electrical Resistivity 6×10⁻⁷ Ω·m23.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

45 / 100
40 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.3 V

Manufacturability

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

Machinability

32 / 100
6 / 100

Machinability Rating (AISI 1212 = 100 %)

42%
40%

Formability (cold)

12 / 100
20 / 100

Same in both: Weldability 10 / 100 · Brazeability / Solderability 40 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 53 MJ/kg22,786 BTU/lb · Embodied Carbon (primary production) 4.7 kg CO₂/kg · Embodied Water 130 L/kg15.6 gal/lb · Typical Recycled Content 40%

Strength versus weight

Yield strength against density for every stainless steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

3005007001,0001,5002,0007.27.47.67.888.2Density (g/cm³)Yield strength (MPa) — log scale1.3549

1.3549 +C vs 1.3549 QT 500 (54-57 HRC) — frequently asked

Is 1.3549 QT 500 (54-57 HRC) stronger than 1.3549 +C?

Yes. 1.3549 QT 500 (54-57 HRC) has a typical yield strength of 1,700 MPa (247 ksi) against 620 MPa (89.9 ksi) for 1.3549 +C — about 174% more. Tensile strength is 1,850 MPa (268 ksi) vs 880 MPa (128 ksi).

Which condition does FabDigit quote by default, +C or QT 500 (54-57 HRC)?

A is the default 1.3549 condition in the FabDigit quote flow (neither +C nor QT 500 (54-57 HRC)). 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.

Which is easier to machine, 1.3549 +C or 1.3549 QT 500 (54-57 HRC)?

1.3549 +C. Its machinability rates poor (32/100) against not recommended (6/100) for 1.3549 QT 500 (54-57 HRC).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 1.3549 +C and 1.3549 QT 500 (54-57 HRC) 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.