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Steel 10B21 Annealed vs 10B21-CR

Steel · 10B21 temper comparison

10B21 Annealed and 10B21-CR are two conditions of the same steel grade, 10B21: Annealed versus CR (cold rolled). The chemistry is identical, so every difference below comes from the condition. 10B21-CR is the stronger of the two: yield strength 470 MPa (68.2 ksi) against 250 MPa (36.3 ksi) for 10B21 Annealed, about 88% more; tensile strength follows at 550 MPa (79.8 ksi) vs 400 MPa (58 ksi). In exchange, 10B21 Annealed is the more ductile: elongation 34% versus 15% for 10B21-CR, and 10B21-CR is harder (163 HB vs 111 HB). 10B21 Annealed runs hotter in service (400°C vs 300°C continuous). On the shop floor, 10B21-CR machines more easily (68 vs 55 out of 100).

10B21 AnnealedChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

10B21-CRChoose it when strength drives the design, or when the part is machined in volume.

10B21 Annealed vs 10B21-CR: properties

10B21 Annealed10B21-CR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

400 MPa58 ksi
550 MPa79.8 ksi

Yield Strength (0.2% offset)

250 MPa36.3 ksi
470 MPa68.2 ksi

Elongation at Break

34%
15%

Reduction in Area

60%
45%

Shear Strength

275 MPa39.9 ksi
340 MPa49.3 ksi

Fatigue Strength (Endurance Limit)

190 MPa27.6 ksi
250 MPa36.3 ksi

Charpy V-Notch Impact (RT)

80 J59 ft·lbf
40 J29.5 ft·lbf

Hardness, Brinell

111 HB
163 HB

Hardness, Rockwell B

62 HRB
84 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 · Fracture Toughness (K_IC) 90 MPa·√m81.9 ksi·√in

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,465°C2,669 °F · Liquidus Temperature 1,510°C2,750 °F

Thermal

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

Max Service Temperature (continuous)

400°C752 °F
300°C572 °F

Same in both: Thermal Conductivity 51.9 W/m·K30 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.7 µm/m·K6.5 µin/in·°F · Latent Heat of Fusion 247 J/g106 BTU/lb · Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 10.8 % IACS · Electrical Resistivity 1.6×10⁻⁷ Ω·m6.3 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 10 / 100

Manufacturability

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

Machinability

55 / 100
68 / 100

Machinability Rating (AISI 1212 = 100 %)

58%
70%

Weldability

88 / 100
85 / 100

Formability (cold)

92 / 100
60 / 100

Same in both: Brazeability / Solderability 70 / 100 · Polishability 45 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 1.9 kg CO₂/kg · Embodied Water 40 L/kg4.8 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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale10B21

10B21 Annealed vs 10B21-CR — frequently asked

Is 10B21-CR stronger than 10B21 Annealed?

Yes. 10B21-CR has a typical yield strength of 470 MPa (68.2 ksi) against 250 MPa (36.3 ksi) for 10B21 Annealed — about 88% more. Tensile strength is 550 MPa (79.8 ksi) vs 400 MPa (58 ksi).

Which condition does FabDigit quote by default, Annealed or CR?

HR is the default 10B21 condition in the FabDigit quote flow (neither Annealed nor CR). 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, 10B21 Annealed or 10B21-CR?

10B21-CR, by a small margin. Both rate good for machinability — 68/100 against 55/100 for 10B21 Annealed.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 10B21 Annealed and 10B21-CR 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.