Steel NAK55 Annealed vs NAK55 Q&T
Steel · NAK55 temper comparison
NAK55 Annealed and NAK55 Q&T are two conditions of the same steel grade, NAK55: Annealed versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. NAK55 Q&T is the stronger of the two: yield strength 1,120 MPa (162 ksi) against 560 MPa (81.2 ksi) for NAK55 Annealed, about 100% more; tensile strength follows at 1,290 MPa (187 ksi) vs 800 MPa (116 ksi). In exchange, NAK55 Annealed is the more ductile: elongation 20% versus 9% for NAK55 Q&T, and NAK55 Q&T is harder (385 HB vs 245 HB). On the shop floor, NAK55 Annealed machines more easily (very good vs fair).
NAK55 AnnealedChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
NAK55 Q&TChoose it when strength drives the design.
NAK55 Annealed vs NAK55 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, Brinell
Hardness, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 206 GPa29.9 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 165 GPa23.9 Msi · Poisson's Ratio 0.29
Physical
Density and transition temperatures.
Same in both: Density 7.8 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,480°C2,696 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 39 W/m·K22.5 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.4 µm/m·K6.9 µin/in·°F · Max Service Temperature (continuous) 430°C806 °F · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Resistivity 2.6×10⁻⁷ Ω·m10.2 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: 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 40 / 100 · Brazeability / Solderability 30 / 100 · Polishability 45 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 34 MJ/kg14,617 BTU/lb · Embodied Carbon (primary production) 2.5 kg CO₂/kg · Embodied Water 55 L/kg6.6 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.
NAK55 Annealed vs NAK55 Q&T — frequently asked
Is NAK55 Q&T stronger than NAK55 Annealed?
Yes. NAK55 Q&T has a typical yield strength of 1,120 MPa (162 ksi) against 560 MPa (81.2 ksi) for NAK55 Annealed — about 100% more. Tensile strength is 1,290 MPa (187 ksi) vs 800 MPa (116 ksi).
Which condition does FabDigit quote by default, Annealed or Q&T?
Annealed is the default NAK55 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.
Which is easier to machine, NAK55 Annealed or NAK55 Q&T?
NAK55 Annealed. Its machinability rates very good (70/100) against fair (52/100) for NAK55 Q&T.
Ready to make it?
Upload a CAD file and FabDigit prices the part in NAK55 Annealed and NAK55 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.