Steel AHSS-DP780 vs AHSS-HR
Steel · AHSS temper comparison
AHSS-DP780 and AHSS-HR are two conditions of the same steel grade, AHSS: DP780 (dual phase, 780 MPa min tensile class) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. AHSS-DP780 is the stronger of the two: yield strength 510 MPa (74 ksi) against 400 MPa (58 ksi) for AHSS-HR, about 28% more; tensile strength follows at 820 MPa (119 ksi) vs 620 MPa (89.9 ksi). In exchange, AHSS-HR is the more ductile: elongation 24% versus 18% for AHSS-DP780, and AHSS-DP780 is harder (240 HB vs 185 HB).
AHSS-DP780Choose it when strength drives the design.
AHSS-HRChoose it when the part is bent, formed or impact-loaded.
AHSS-DP780 vs AHSS-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
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 207 GPa30 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) 1,500°C2,732 °F · Liquidus Temperature 1,520°C2,768 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
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 · Max Service Temperature (continuous) 200°C392 °F · Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
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
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Brazeability / Solderability 60 / 100 · Polishability 55 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 27 MJ/kg11,608 BTU/lb · Embodied Carbon (primary production) 2.2 kg CO₂/kg · Embodied Water 45 L/kg5.4 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.
AHSS-DP780 vs AHSS-HR — frequently asked
Is AHSS-DP780 stronger than AHSS-HR?
Yes. AHSS-DP780 has a typical yield strength of 510 MPa (74 ksi) against 400 MPa (58 ksi) for AHSS-HR — about 28% more. Tensile strength is 820 MPa (119 ksi) vs 620 MPa (89.9 ksi).
Which condition does FabDigit quote by default, DP780 or HR?
HR is the default AHSS 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, AHSS-DP780 or AHSS-HR?
AHSS-HR, by a small margin. Both rate fair for machinability — 45/100 against 38/100 for AHSS-DP780.
Ready to make it?
Upload a CAD file and FabDigit prices the part in AHSS-DP780 and AHSS-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.