Steel SKD11 Nitrided vs SKD11 Q&T
Steel · SKD11 temper comparison
SKD11 Nitrided and SKD11 Q&T are two conditions of the same steel grade, SKD11: Nitrided versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. Both yield at about 1,800 MPa — the mechanical properties are the same, and the difference is in how the stock is processed and what it is certified to (Nitrided versus quenched and tempered). SKD11 Q&T is the more ductile: elongation 1.5% versus 1% for SKD11 Nitrided, and SKD11 Nitrided is harder (1,050 HV vs 680 HV). SKD11 Nitrided runs hotter in service (450°C vs 200°C continuous). On the shop floor, SKD11 Q&T welds better (poor vs not recommended).
SKD11 NitridedChoose it when the part sees heat.
SKD11 Q&TChoose it when the part is bent, formed or impact-loaded, or when it will be welded.
SKD11 Nitrided vs SKD11 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)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Hardness, Brinell 225 HB · Hardness, Rockwell B 98 HRB · Hardness, Rockwell C 59 HRC
Physical
Density and transition temperatures.
Same in both: Density 7.7 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,250°C2,282 °F · Liquidus Temperature 1,420°C2,588 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 20 W/m·K11.6 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 10.9 µm/m·K6.1 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -30°C-22 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.35 V
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 25 / 100 · Brazeability / Solderability 40 / 100 · Polishability 80 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 36 MJ/kg15,477 BTU/lb · Embodied Carbon (primary production) 2.6 kg CO₂/kg · Embodied Water 70 L/kg8.4 gal/lb · Typical Recycled Content 40%
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.
SKD11 Nitrided vs SKD11 Q&T — frequently asked
What is the difference between SKD11 Nitrided and SKD11 Q&T?
SKD11 Nitrided and SKD11 Q&T are two conditions of the same steel grade, SKD11: Nitrided versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. Both yield at about 1,800 MPa — the mechanical properties are the same, and the difference is in how the stock is processed and what it is certified to (Nitrided versus quenched and tempered).
Which condition does FabDigit quote by default, Nitrided or Q&T?
Annealed is the default SKD11 condition in the FabDigit quote flow (neither Nitrided 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.
Which is easier to machine, SKD11 Nitrided or SKD11 Q&T?
SKD11 Q&T, by a small margin. Both rate not recommended for machinability — 8/100 against 3/100 for SKD11 Nitrided; for welding the order is SKD11 Q&T first (poor, 20/100) then SKD11 Nitrided (not recommended, 5/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in SKD11 Nitrided and SKD11 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.