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Steel 4118-CD vs 4118-HR

Steel · 4118 temper comparison

4118-CD and 4118-HR are two conditions of the same steel grade, 4118: CD (cold drawn) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. 4118-CD is the stronger of the two: yield strength 540 MPa (78.3 ksi) against 380 MPa (55.1 ksi) for 4118-HR, about 42% more; tensile strength follows at 640 MPa (92.8 ksi) vs 570 MPa (82.7 ksi). In exchange, 4118-HR is the more ductile: elongation 24% versus 13% for 4118-CD, and 4118-CD is harder (187 HB vs 163 HB).

4118-CDChoose it when strength drives the design.

4118-HRChoose it when the part is bent, formed or impact-loaded.

4118-CD vs 4118-HR: properties

4118-CD4118-HR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

640 MPa92.8 ksi
570 MPa82.7 ksi

Yield Strength (0.2% offset)

540 MPa78.3 ksi
380 MPa55.1 ksi

Elongation at Break

13%
24%

Reduction in Area

42%
50%

Shear Strength

350 MPa50.8 ksi
375 MPa54.4 ksi

Fatigue Strength (Endurance Limit)

290 MPa42.1 ksi
260 MPa37.7 ksi

Fracture Toughness (K_IC)

100 MPa·√m91 ksi·√in
95 MPa·√m86.5 ksi·√in

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
55 J40.6 ft·lbf

Hardness, Brinell

187 HB
163 HB

Hardness, Rockwell B

90 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

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 1,505°C2,741 °F

Thermal

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

Same in both: Thermal Conductivity 42 W/m·K24.3 BTU/hr·ft·°F · Specific Heat Capacity 475 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.2 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 247 J/g106 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 7.8 % 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) -0.62 V · Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

64 / 100
56 / 100

Machinability Rating (AISI 1212 = 100 %)

70%
60%

Formability (cold)

40 / 100
52 / 100

Same in both: Weldability 60 / 100 · Brazeability / Solderability 60 / 100 · Polishability 50 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 24 MJ/kg10,318 BTU/lb · Embodied Carbon (primary production) 1.9 kg CO₂/kg · Embodied Water 60 L/kg7.2 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 scale4118

4118-CD vs 4118-HR — frequently asked

Is 4118-CD stronger than 4118-HR?

Yes. 4118-CD has a typical yield strength of 540 MPa (78.3 ksi) against 380 MPa (55.1 ksi) for 4118-HR — about 42% more. Tensile strength is 640 MPa (92.8 ksi) vs 570 MPa (82.7 ksi).

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

ANN is the default 4118 condition in the FabDigit quote flow (neither CD 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, 4118-CD or 4118-HR?

4118-CD, by a small margin. Both rate good for machinability — 64/100 against 56/100 for 4118-HR.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 4118-CD and 4118-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.