Steel P355GH-HR vs P355GH Q&T
Steel · P355GH temper comparison
P355GH-HR and P355GH Q&T are two conditions of the same steel grade, P355GH: HR (hot rolled) versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. P355GH Q&T is the stronger of the two: yield strength 450 MPa (65.3 ksi) against 385 MPa (55.8 ksi) for P355GH-HR, about 17% more; tensile strength follows at 600 MPa (87 ksi) vs 550 MPa (79.8 ksi). P355GH Q&T is harder — 185 HB against 165 HB for P355GH-HR — which matters for wear surfaces and threads.
P355GH Q&TChoose it when strength drives the design, or when surface hardness matters.
P355GH-HR vs P355GH Q&T: 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)
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
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 · Elongation at Break 24% · Reduction in Area 50% · Compressive Strength 385 MPa55.8 ksi · Shear Strength 340 MPa49.3 ksi · Fracture Toughness (K_IC) 100 MPa·√m91 ksi·√in · Hardness, Rockwell B 85 HRB · Hardness, Vickers 173 HV
Physical
Density and transition temperatures.
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,460°C2,660 °F · Liquidus Temperature 1,510°C2,750 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 48 W/m·K27.7 BTU/hr·ft·°F · Specific Heat Capacity 461 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 260 J/g112 BTU/lb · Min Service Temperature -10°C14 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 8.2 % IACS · Electrical Resistivity 2.1×10⁻⁷ Ω·m8.27 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.62 V · Corrosion Resistance 12 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability Rating (AISI 1212 = 100 %)
Formability (cold)
Same in both: Machinability 58 / 100 · Weldability 85 / 100 · Brazeability / Solderability 50 / 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 40 L/kg4.8 gal/lb · Typical Recycled Content 25%
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.
P355GH-HR vs P355GH Q&T — frequently asked
Is P355GH Q&T stronger than P355GH-HR?
Yes. P355GH Q&T has a typical yield strength of 450 MPa (65.3 ksi) against 385 MPa (55.8 ksi) for P355GH-HR — about 17% more. Tensile strength is 600 MPa (87 ksi) vs 550 MPa (79.8 ksi).
Which condition does FabDigit quote by default, HR or Q&T?
HR is the default P355GH 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 P355GH-HR over P355GH Q&T?
Pick P355GH Q&T when strength drives the design, or when surface hardness matters.
Ready to make it?
Upload a CAD file and FabDigit prices the part in P355GH-HR and P355GH Q&T 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.