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Steel C60 +AC vs C60-HR

Steel · C60 temper comparison

C60 +AC and C60-HR are two conditions of the same steel grade, C60: +AC (spheroidize annealed) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. C60-HR is the stronger of the two: yield strength 370 MPa (53.7 ksi) against 340 MPa (49.3 ksi) for C60 +AC, about 9% more; tensile strength follows at 675 MPa (97.9 ksi) vs 580 MPa (84.1 ksi). In exchange, C60 +AC is the more ductile: elongation 26% versus 17% for C60-HR, and C60-HR is harder (201 HB vs 170 HB).

C60 +ACChoose it when the part is bent, formed or impact-loaded.

C60-HRChoose it when strength drives the design.

C60 +AC vs C60-HR: properties

C60 +ACC60-HR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

580 MPa84.1 ksi
675 MPa97.9 ksi

Yield Strength (0.2% offset)

340 MPa49.3 ksi
370 MPa53.7 ksi

Elongation at Break

26%
17%

Reduction in Area

50%
38%

Compressive Strength

345 MPa50 ksi
375 MPa54.4 ksi

Shear Strength

350 MPa50.8 ksi
405 MPa58.7 ksi

Fatigue Strength (Endurance Limit)

265 MPa38.4 ksi
300 MPa43.5 ksi

Fracture Toughness (K_IC)

60 MPa·√m54.6 ksi·√in
52 MPa·√m47.3 ksi·√in

Charpy V-Notch Impact (RT)

18 J13.3 ft·lbf
12 J8.9 ft·lbf

Hardness, Brinell

170 HB
201 HB

Hardness, Rockwell B

86 HRB
94 HRB

Hardness, Vickers

178 HV
211 HV

Same in both: Elastic (Young's) Modulus 207 GPa30 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Hardness, Rockwell C 20 HRC

Physical

Density and transition temperatures.

Same in both: Density 7.84 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.

Thermal Conductivity

50 W/m·K28.9 BTU/hr·ft·°F
48 W/m·K27.7 BTU/hr·ft·°F

Same in both: Specific Heat Capacity 475 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.3 µm/m·K6.3 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 300°C572 °F · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

9.8 % IACS
9.6 % IACS

Electrical Resistivity

1.76×10⁻⁷ Ω·m6.93 µΩ·in
1.8×10⁻⁷ Ω·m7.09 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.65 V · Corrosion Resistance 10 / 100

Manufacturability

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

Machinability

55 / 100
47 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
58%

Weldability

25 / 100
20 / 100

Formability (cold)

55 / 100
30 / 100

Same in both: Brazeability / Solderability 55 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 2.1 kg CO₂/kg · Embodied Water 55 L/kg6.6 gal/lb · Typical Recycled Content 25%

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 scaleC60

C60 +AC vs C60-HR — frequently asked

Is C60-HR stronger than C60 +AC?

Yes. C60-HR has a typical yield strength of 370 MPa (53.7 ksi) against 340 MPa (49.3 ksi) for C60 +AC — about 9% more. Tensile strength is 675 MPa (97.9 ksi) vs 580 MPa (84.1 ksi).

Which condition does FabDigit quote by default, +AC or HR?

+N is the default C60 condition in the FabDigit quote flow (neither +AC nor HR). 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, C60 +AC or C60-HR?

C60 +AC. Its machinability rates good (55/100) against fair (47/100) for C60-HR; for welding the order is C60 +AC first (poor, 25/100) then C60-HR (poor, 20/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C60 +AC and C60-HR 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.