Steel A356 Grade 5 N+T+SPWHT vs A356 Grade 5 Q&T
Steel · A356 Grade 5 temper comparison
A356 Grade 5 N+T+SPWHT and A356 Grade 5 Q&T are two conditions of the same steel grade, A356 Grade 5: N+T+SPWHT (N+T + simulated post-weld heat treatment) versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. A356 Grade 5 Q&T is the stronger of the two: yield strength 450 MPa (65.3 ksi) against 320 MPa (46.4 ksi) for A356 Grade 5 N+T+SPWHT, about 41% more; tensile strength follows at 620 MPa (89.9 ksi) vs 520 MPa (75.4 ksi). In exchange, A356 Grade 5 N+T+SPWHT is the more ductile: elongation 26% versus 21% for A356 Grade 5 Q&T, and A356 Grade 5 Q&T is harder (195 HB vs 160 HB).
A356 Grade 5 N+T+SPWHTChoose it when the part is bent, formed or impact-loaded.
A356 Grade 5 Q&TChoose it when strength drives the design.
A356 Grade 5 N+T+SPWHT vs A356 Grade 5 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.
A356 Grade 5 N+T+SPWHTA356 Grade 5 Q&T
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 207 GPa30 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Reduction in Area 50%
Physical
Density and transition temperatures.
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,450°C2,642 °F · Liquidus Temperature 1,505°C2,741 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 40 W/m·K23.1 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.3 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 260 J/g112 BTU/lb · Min Service Temperature -30°C-22 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 7.8 % IACS · Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.62 V · Corrosion Resistance 20 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Formability (cold)
Same in both: Weldability 55 / 100 · Castability 70 / 100 · Brazeability / Solderability 45 / 100 · Polishability 50 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 27 MJ/kg11,608 BTU/lb · Embodied Carbon (primary production) 2.1 kg CO₂/kg · Embodied Water 55 L/kg6.6 gal/lb · Typical Recycled Content 75%
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.
A356 Grade 5 N+T+SPWHT vs A356 Grade 5 Q&T — frequently asked
Is A356 Grade 5 Q&T stronger than A356 Grade 5 N+T+SPWHT?
Yes. A356 Grade 5 Q&T has a typical yield strength of 450 MPa (65.3 ksi) against 320 MPa (46.4 ksi) for A356 Grade 5 N+T+SPWHT — about 41% more. Tensile strength is 620 MPa (89.9 ksi) vs 520 MPa (75.4 ksi).
Which condition does FabDigit quote by default, N+T+SPWHT or Q&T?
N+T is the default A356 Grade 5 condition in the FabDigit quote flow (neither N+T+SPWHT nor Q&T). 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 A356 Grade 5 N+T+SPWHT over A356 Grade 5 Q&T?
Pick A356 Grade 5 N+T+SPWHT when the part is bent, formed or impact-loaded. Pick A356 Grade 5 Q&T when strength drives the design.
Ready to make it?
Upload a CAD file and FabDigit prices the part in A356 Grade 5 N+T+SPWHT and A356 Grade 5 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.