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Steel S355J2G3-C vs S355J2G3-QT

Steel · S355J2G3 temper comparison

S355J2G3-C and S355J2G3-QT are two conditions of the same steel grade, S355J2G3: C versus QT (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. S355J2G3-C is the stronger of the two: yield strength 470 MPa (68.2 ksi) against 430 MPa (62.4 ksi) for S355J2G3-QT, about 9% more; tensile strength follows at 600 MPa (87 ksi) vs 570 MPa (82.7 ksi). In exchange, S355J2G3-QT is the more ductile: elongation 22% versus 12% for S355J2G3-C, and S355J2G3-C is harder (185 HB vs 175 HB). S355J2G3-QT runs hotter in service (400°C vs 300°C continuous). On the shop floor, S355J2G3-C machines more easily (very good vs good).

S355J2G3-CChoose it when strength drives the design, or when the part is machined in volume.

S355J2G3-QTChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

S355J2G3-C vs S355J2G3-QT: properties

S355J2G3-CS355J2G3-QT

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

600 MPa87 ksi
570 MPa82.7 ksi

Yield Strength (0.2% offset)

470 MPa68.2 ksi
430 MPa62.4 ksi

Elongation at Break

12%
22%

Reduction in Area

42%
55%

Compressive Strength

480 MPa69.6 ksi
430 MPa62.4 ksi

Shear Strength

370 MPa53.7 ksi
360 MPa52.2 ksi

Fatigue Strength (Endurance Limit)

270 MPa39.2 ksi
265 MPa38.4 ksi

Fracture Toughness (K_IC)

85 MPa·√m77.4 ksi·√in
125 MPa·√m114 ksi·√in

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
150 J111 ft·lbf

Hardness, Brinell

185 HB
175 HB

Hardness, Rockwell B

90 HRB
87 HRB

Hardness, Vickers

195 HV
184 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) 1,425°C2,597 °F · Liquidus Temperature 1,510°C2,750 °F

Thermal

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

Thermal Conductivity

45 W/m·K26 BTU/hr·ft·°F
44 W/m·K25.4 BTU/hr·ft·°F

Max Service Temperature (continuous)

300°C572 °F
400°C752 °F

Min Service Temperature

-20°C-4 °F
-40°C-40 °F

Same in both: 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

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 10 % IACS · Electrical Resistivity 1.7×10⁻⁷ Ω·m6.69 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

70 / 100
55 / 100

Machinability Rating (AISI 1212 = 100 %)

70%
55%

Weldability

80 / 100
82 / 100

Formability (cold)

45 / 100
58 / 100

Same in both: Castability 40 / 100 · Brazeability / Solderability 60 / 100 · Polishability 45 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 1.9 kg CO₂/kg · Embodied Water 45 L/kg5.4 gal/lb · Typical Recycled Content 30%

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 scaleS355J2G3

S355J2G3-C vs S355J2G3-QT — frequently asked

Is S355J2G3-C stronger than S355J2G3-QT?

Yes. S355J2G3-C has a typical yield strength of 470 MPa (68.2 ksi) against 430 MPa (62.4 ksi) for S355J2G3-QT — about 9% more. Tensile strength is 600 MPa (87 ksi) vs 570 MPa (82.7 ksi).

Which condition does FabDigit quote by default, C or QT?

N is the default S355J2G3 condition in the FabDigit quote flow (neither C nor QT). 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, S355J2G3-C or S355J2G3-QT?

S355J2G3-C. Its machinability rates very good (70/100) against good (55/100) for S355J2G3-QT.

Ready to make it?

Upload a CAD file and FabDigit prices the part in S355J2G3-C and S355J2G3-QT 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.