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Steel 8630 Annealed vs 8630 Q&T

Steel · 8630 temper comparison

8630 Annealed and 8630 Q&T are two conditions of the same steel grade, 8630: Annealed versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. 8630 Q&T is the stronger of the two: yield strength 860 MPa (125 ksi) against 372 MPa (54 ksi) for 8630 Annealed, about 131% more; tensile strength follows at 1,000 MPa (145 ksi) vs 565 MPa (81.9 ksi). In exchange, 8630 Annealed is the more ductile: elongation 29% versus 18% for 8630 Q&T, and 8630 Q&T is harder (293 HB vs 156 HB). On the shop floor, 8630 Annealed machines more easily (good vs fair).

8630 AnnealedChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

8630 Q&TChoose it when strength drives the design.

8630 Annealed vs 8630 Q&T: properties

8630 Annealed8630 Q&T

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

565 MPa81.9 ksi
1,000 MPa145 ksi

Yield Strength (0.2% offset)

372 MPa54 ksi
860 MPa125 ksi

Elongation at Break

29%
18%

Reduction in Area

59%
55%

Shear Strength

450 MPa65.3 ksi
620 MPa89.9 ksi

Fatigue Strength (Endurance Limit)

275 MPa39.9 ksi
470 MPa68.2 ksi

Hardness, Brinell

156 HB
293 HB

Hardness, Rockwell B

81 HRB
93 HRB

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Charpy V-Notch Impact (RT) 60 J44.3 ft·lbf

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,500°C2,732 °F

Thermal

How each material carries heat and how hot it can run.

Same in both: Thermal Conductivity 43 W/m·K24.8 BTU/hr·ft·°F · Specific Heat Capacity 477 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 250 J/g107 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 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) -0.61 V · Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

65 / 100
50 / 100

Machinability Rating (AISI 1212 = 100 %)

70%
55%

Formability (cold)

55 / 100
40 / 100

Same in both: Weldability 40 / 100 · Castability 55 / 100 · Brazeability / Solderability 55 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 30 MJ/kg12,898 BTU/lb · Embodied Carbon (primary production) 2.2 kg CO₂/kg · Embodied Water 60 L/kg7.2 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 scale8630

8630 Annealed vs 8630 Q&T — frequently asked

Is 8630 Q&T stronger than 8630 Annealed?

Yes. 8630 Q&T has a typical yield strength of 860 MPa (125 ksi) against 372 MPa (54 ksi) for 8630 Annealed — about 131% more. Tensile strength is 1,000 MPa (145 ksi) vs 565 MPa (81.9 ksi).

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

HR is the default 8630 condition in the FabDigit quote flow (neither Annealed 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, 8630 Annealed or 8630 Q&T?

8630 Annealed. Its machinability rates good (65/100) against fair (50/100) for 8630 Q&T.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 8630 Annealed and 8630 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.