Steel SKD61 Nitrided vs SKD61 Q&T
Steel · SKD61 temper comparison
SKD61 Nitrided and SKD61 Q&T are two conditions of the same steel grade, SKD61: Nitrided versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. Both yield at about 1,300 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). SKD61 Q&T is the more ductile: elongation 12% versus 9% for SKD61 Nitrided, and SKD61 Nitrided is harder (430 HB vs 215 HB). On the shop floor, SKD61 Q&T machines more easily (poor vs not recommended) and SKD61 Q&T welds better (fair vs not recommended).
SKD61 Q&TChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
SKD61 Nitrided vs SKD61 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.
Elastic (Young's) Modulus
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Vickers
Same in both: Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Tensile Strength (Ultimate) 1,500 MPa218 ksi · Shear Strength 900 MPa131 ksi · Hardness, Rockwell C 46 HRC
Physical
Density and transition temperatures.
Same in both: Density 7.8 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,427°C2,601 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 24.5 W/m·K14.2 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11 µm/m·K6.1 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 560°C1,040 °F · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 3.3 % IACS · Electrical Resistivity 5.2×10⁻⁷ Ω·m20.5 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.6 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: 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) 2.8 kg CO₂/kg · Embodied Water 65 L/kg7.8 gal/lb · Typical Recycled Content 35%
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.
SKD61 Nitrided vs SKD61 Q&T — frequently asked
What is the difference between SKD61 Nitrided and SKD61 Q&T?
SKD61 Nitrided and SKD61 Q&T are two conditions of the same steel grade, SKD61: Nitrided versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. Both yield at about 1,300 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 SKD61 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, SKD61 Nitrided or SKD61 Q&T?
SKD61 Q&T. Its machinability rates poor (20/100) against not recommended (5/100) for SKD61 Nitrided; for welding the order is SKD61 Q&T first (fair, 35/100) then SKD61 Nitrided (not recommended, 5/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in SKD61 Nitrided and SKD61 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.