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Steel CP800-CR vs CP800-HR

Steel · CP800 temper comparison

CP800-CR and CP800-HR are two conditions of the same steel grade, CP800: CR (cold rolled) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. CP800-HR is the stronger of the two: yield strength 660 MPa (95.7 ksi) against 620 MPa (89.9 ksi) for CP800-CR, about 6% more. CP800-HR runs hotter in service (250°C vs 200°C continuous).

CP800-HRChoose it when strength drives the design, or when the part sees heat.

CP800-CR vs CP800-HR: properties

CP800-CRCP800-HR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

840 MPa122 ksi
830 MPa120 ksi

Yield Strength (0.2% offset)

620 MPa89.9 ksi
660 MPa95.7 ksi

Elongation at Break

13%
14%

Reduction in Area

45%
48%

Compressive Strength

840 MPa122 ksi
830 MPa120 ksi

Shear Strength

520 MPa75.4 ksi
515 MPa74.7 ksi

Fatigue Strength (Endurance Limit)

380 MPa55.1 ksi
385 MPa55.8 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
60 MPa·√m54.6 ksi·√in

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
50 J36.9 ft·lbf

Hardness, Brinell

250 HB
245 HB

Hardness, Rockwell B

100 HRB
99 HRB

Hardness, Rockwell C

25 HRC
24 HRC

Hardness, Vickers

265 HV
258 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.3

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,460°C2,660 °F · Liquidus Temperature 1,510°C2,750 °F

Thermal

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

Thermal Conductivity

38 W/m·K22 BTU/hr·ft·°F
40 W/m·K23.1 BTU/hr·ft·°F

Max Service Temperature (continuous)

200°C392 °F
250°C482 °F

Same in both: Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

7.8 % IACS
8 % IACS

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 µΩ·in
2.15×10⁻⁷ Ω·m8.46 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

12 / 100
10 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.62 V

Manufacturability

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

Machinability

35 / 100
37 / 100

Machinability Rating (AISI 1212 = 100 %)

35%
37%

Formability (cold)

45 / 100
50 / 100

Same in both: Weldability 70 / 100 · Brazeability / Solderability 55 / 100 · Polishability 45 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 28 MJ/kg12,038 BTU/lb · Embodied Carbon (primary production) 2.2 kg CO₂/kg · Embodied Water 45 L/kg5.4 gal/lb · Typical Recycled Content 20%

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 scaleCP800

CP800-CR vs CP800-HR — frequently asked

Is CP800-HR stronger than CP800-CR?

Yes. CP800-HR has a typical yield strength of 660 MPa (95.7 ksi) against 620 MPa (89.9 ksi) for CP800-CR — about 6% more. Tensile strength is 830 MPa (120 ksi) vs 840 MPa (122 ksi).

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

CR is the default CP800 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.

When should I choose CP800-CR over CP800-HR?

Pick CP800-HR when strength drives the design, or when the part sees heat.

Ready to make it?

Upload a CAD file and FabDigit prices the part in CP800-CR and CP800-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.