Steel Mild Steel-CD vs Mild Steel-HR
Steel · Mild Steel temper comparison
Mild Steel-CD and Mild Steel-HR are two conditions of the same steel grade, Mild Steel: CD (cold drawn) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. Mild Steel-CD is the stronger of the two: yield strength 370 MPa (53.7 ksi) against 250 MPa (36.3 ksi) for Mild Steel-HR, about 48% more; tensile strength follows at 440 MPa (63.8 ksi) vs 400 MPa (58 ksi). In exchange, Mild Steel-HR is the more ductile: elongation 24% versus 15% for Mild Steel-CD, and Mild Steel-CD is harder (130 HB vs 120 HB). On the shop floor, Mild Steel-CD machines more easily (very good vs good).
Mild Steel-CDChoose it when strength drives the design, or when the part is machined in volume.
Mild Steel-HRChoose it when the part is bent, formed or impact-loaded.
Mild Steel-CD vs Mild Steel-HR: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 79 GPa11.5 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Compressive Strength 250 MPa36.3 ksi · Fracture Toughness (K_IC) 110 MPa·√m100 ksi·√in · Hardness, Vickers 126 HV
Physical
Density and transition temperatures.
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,495°C2,723 °F · Liquidus Temperature 1,520°C2,768 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 51 W/m·K29.5 BTU/hr·ft·°F · Specific Heat Capacity 480 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 247 J/g106 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -20°C-4 °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) -0.65 V · Corrosion Resistance 10 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Castability 45 / 100 · Brazeability / Solderability 80 / 100 · Polishability 55 / 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 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.
Mild Steel-CD vs Mild Steel-HR — frequently asked
Is Mild Steel-CD stronger than Mild Steel-HR?
Yes. Mild Steel-CD has a typical yield strength of 370 MPa (53.7 ksi) against 250 MPa (36.3 ksi) for Mild Steel-HR — about 48% more. Tensile strength is 440 MPa (63.8 ksi) vs 400 MPa (58 ksi).
Which condition does FabDigit quote by default, CD or HR?
HR is the default Mild Steel 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.
Which is easier to machine, Mild Steel-CD or Mild Steel-HR?
Mild Steel-CD. Its machinability rates very good (72/100) against good (60/100) for Mild Steel-HR.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Mild Steel-CD and Mild Steel-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.