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Steel DD13-HR vs DD13 HR-SP

Steel · DD13 temper comparison

DD13-HR and DD13 HR-SP are two conditions of the same steel grade, DD13: HR (hot rolled) versus HR-SP (hot rolled, skin-passed). The chemistry is identical, so every difference below comes from the condition. DD13 HR-SP is the stronger of the two: yield strength 245 MPa (35.5 ksi) against 230 MPa (33.4 ksi) for DD13-HR, about 7% more. DD13 HR-SP is harder — 116 HV against 110 HV for DD13-HR — which matters for wear surfaces and threads.

DD13 HR-SPChoose it when strength drives the design, or when surface hardness matters.

DD13-HR vs DD13 HR-SP: properties

DD13-HRDD13 HR-SP

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

340 MPa49.3 ksi
345 MPa50 ksi

Yield Strength (0.2% offset)

230 MPa33.4 ksi
245 MPa35.5 ksi

Elongation at Break

36%
34%

Reduction in Area

65%
63%

Compressive Strength

230 MPa33.4 ksi
245 MPa35.5 ksi

Shear Strength

230 MPa33.4 ksi
235 MPa34.1 ksi

Fatigue Strength (Endurance Limit)

160 MPa23.2 ksi
165 MPa23.9 ksi

Charpy V-Notch Impact (RT)

60 J44.3 ft·lbf
55 J40.6 ft·lbf

Hardness, Brinell

105 HB
110 HB

Hardness, Rockwell B

58 HRB
62 HRB

Hardness, Vickers

110 HV
116 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 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) 1,495°C2,723 °F · Liquidus Temperature 1,525°C2,777 °F

Thermal

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

Same in both: Thermal Conductivity 52 W/m·K30 BTU/hr·ft·°F · 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 · Max Service Temperature (continuous) 350°C662 °F · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 11 % 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

58 / 100
60 / 100

Machinability Rating (AISI 1212 = 100 %)

55%
57%

Weldability

96 / 100
95 / 100

Formability (cold)

90 / 100
88 / 100

Same in both: Brazeability / Solderability 65 / 100 · Polishability 40 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 23 MJ/kg9,888 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Embodied Water 35 L/kg4.2 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 scaleDD13

DD13-HR vs DD13 HR-SP — frequently asked

Is DD13 HR-SP stronger than DD13-HR?

Yes. DD13 HR-SP has a typical yield strength of 245 MPa (35.5 ksi) against 230 MPa (33.4 ksi) for DD13-HR — about 7% more. Tensile strength is 345 MPa (50 ksi) vs 340 MPa (49.3 ksi).

Which condition does FabDigit quote by default, HR or HR-SP?

HR is the default DD13 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 DD13-HR over DD13 HR-SP?

Pick DD13 HR-SP when strength drives the design, or when surface hardness matters.

Ready to make it?

Upload a CAD file and FabDigit prices the part in DD13-HR and DD13 HR-SP 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.