Steel S355J2G3-M vs S355J2G3-QT
Steel · S355J2G3 temper comparison
S355J2G3-M and S355J2G3-QT are two conditions of the same steel grade, S355J2G3: M (thermomechanically controlled processed) versus QT (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. S355J2G3-QT is the stronger of the two: yield strength 430 MPa (62.4 ksi) against 400 MPa (58 ksi) for S355J2G3-M, about 8% more; tensile strength follows at 570 MPa (82.7 ksi) vs 510 MPa (74 ksi). In exchange, S355J2G3-M is the more ductile: elongation 25% versus 22% for S355J2G3-QT, and S355J2G3-QT is harder (175 HB vs 155 HB). On the shop floor, S355J2G3-M welds better (excellent vs very good).
S355J2G3-MChoose it when the part is bent, formed or impact-loaded, or when it will be welded.
S355J2G3-QTChoose it when strength drives the design.
S355J2G3-M vs S355J2G3-QT: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
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
Max Service Temperature (continuous)
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 · Min Service Temperature -40°C-40 °F
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
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
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.
S355J2G3-M vs S355J2G3-QT — frequently asked
Is S355J2G3-QT stronger than S355J2G3-M?
Yes. S355J2G3-QT has a typical yield strength of 430 MPa (62.4 ksi) against 400 MPa (58 ksi) for S355J2G3-M — about 8% more. Tensile strength is 570 MPa (82.7 ksi) vs 510 MPa (74 ksi).
Which condition does FabDigit quote by default, M or QT?
N is the default S355J2G3 condition in the FabDigit quote flow (neither M 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 welds better, S355J2G3-M or S355J2G3-QT?
S355J2G3-M. Its weldability rates excellent (92/100) against very good (82/100) for S355J2G3-QT.
Ready to make it?
Upload a CAD file and FabDigit prices the part in S355J2G3-M 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.