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Steel Mild Steel-ANN vs Mild Steel-HR

Steel · Mild Steel temper comparison

Mild Steel-ANN and Mild Steel-HR are two conditions of the same steel grade, Mild Steel: ANN (annealed) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. Mild Steel-HR is the stronger of the two: yield strength 250 MPa (36.3 ksi) against 210 MPa (30.5 ksi) for Mild Steel-ANN, about 19% more; tensile strength follows at 400 MPa (58 ksi) vs 340 MPa (49.3 ksi). In exchange, Mild Steel-ANN is the more ductile: elongation 38% versus 24% for Mild Steel-HR, and Mild Steel-HR is harder (120 HB vs 100 HB).

Mild Steel-ANNChoose it when the part is bent, formed or impact-loaded.

Mild Steel-HRChoose it when strength drives the design.

Mild Steel-ANN vs Mild Steel-HR: properties

Mild Steel-ANNMild Steel-HR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

340 MPa49.3 ksi
400 MPa58 ksi

Yield Strength (0.2% offset)

210 MPa30.5 ksi
250 MPa36.3 ksi

Elongation at Break

38%
24%

Reduction in Area

60%
45%

Fatigue Strength (Endurance Limit)

170 MPa24.7 ksi
200 MPa29 ksi

Charpy V-Notch Impact (RT)

70 J51.6 ft·lbf
50 J36.9 ft·lbf

Hardness, Brinell

100 HB
120 HB

Hardness, Rockwell B

55 HRB
67 HRB

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 · Shear 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

55 / 100
60 / 100

Machinability Rating (AISI 1212 = 100 %)

55%
60%

Weldability

96 / 100
95 / 100

Formability (cold)

92 / 100
80 / 100

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.

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

Mild Steel-ANN vs Mild Steel-HR — frequently asked

Is Mild Steel-HR stronger than Mild Steel-ANN?

Yes. Mild Steel-HR has a typical yield strength of 250 MPa (36.3 ksi) against 210 MPa (30.5 ksi) for Mild Steel-ANN — about 19% more. Tensile strength is 400 MPa (58 ksi) vs 340 MPa (49.3 ksi).

Which condition does FabDigit quote by default, ANN 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-ANN or Mild Steel-HR?

Mild Steel-HR, by a small margin. Both rate good for machinability — 60/100 against 55/100 for Mild Steel-ANN.

Ready to make it?

Upload a CAD file and FabDigit prices the part in Mild Steel-ANN 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.