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Steel SKD61 Annealed vs SKD61 Q&T

Steel · SKD61 temper comparison

SKD61 Annealed and SKD61 Q&T are two conditions of the same steel grade, SKD61: Annealed versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. SKD61 Q&T is the stronger of the two: yield strength 1,250 MPa (181 ksi) against 415 MPa (60.2 ksi) for SKD61 Annealed, about 3.0 times as much; tensile strength follows at 1,500 MPa (218 ksi) vs 760 MPa (110 ksi). In exchange, SKD61 Annealed is the more ductile: elongation 25% versus 12% for SKD61 Q&T, and SKD61 Q&T is harder (46 HRC vs 19 HRC). SKD61 Q&T runs hotter in service (560°C vs 400°C continuous). On the shop floor, SKD61 Annealed machines more easily (good vs poor).

SKD61 AnnealedChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

SKD61 Q&TChoose it when strength drives the design, or when the part sees heat.

SKD61 Annealed vs SKD61 Q&T: properties

SKD61 AnnealedSKD61 Q&T

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

210 GPa30.5 Msi
211 GPa30.6 Msi

Tensile Strength (Ultimate)

760 MPa110 ksi
1,500 MPa218 ksi

Yield Strength (0.2% offset)

415 MPa60.2 ksi
1,250 MPa181 ksi

Elongation at Break

25%
12%

Reduction in Area

50%
40%

Shear Strength

460 MPa66.7 ksi
900 MPa131 ksi

Fatigue Strength (Endurance Limit)

340 MPa49.3 ksi
640 MPa92.8 ksi

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
18 J13.3 ft·lbf

Hardness, Rockwell C

19 HRC
46 HRC

Hardness, Vickers

225 HV
465 HV

Same in both: Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Hardness, Brinell 215 HB

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.

Max Service Temperature (continuous)

400°C752 °F
560°C1,040 °F

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 · 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).

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 20 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

55 / 100
20 / 100

Machinability Rating (AISI 1212 = 100 %)

55%
15%

Same in both: Weldability 35 / 100 · Formability (cold) 30 / 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) 2.8 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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scaleSKD61

SKD61 Annealed vs SKD61 Q&T — frequently asked

Is SKD61 Q&T stronger than SKD61 Annealed?

Yes. SKD61 Q&T has a typical yield strength of 1,250 MPa (181 ksi) against 415 MPa (60.2 ksi) for SKD61 Annealed — about 3.0 times as much. Tensile strength is 1,500 MPa (218 ksi) vs 760 MPa (110 ksi).

Which condition does FabDigit quote by default, Annealed or Q&T?

Annealed is the default SKD61 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, SKD61 Annealed or SKD61 Q&T?

SKD61 Annealed. Its machinability rates good (55/100) against poor (20/100) for SKD61 Q&T.

Ready to make it?

Upload a CAD file and FabDigit prices the part in SKD61 Annealed 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.