Steel D2 Hardened & Tempered vs D2 Stress Relieved
Steel · D2 temper comparison
D2 Hardened & Tempered and D2 Stress Relieved are two conditions of the same steel grade, D2: Hardened & Tempered (quenched and tempered) versus Stress Relieved. The chemistry is identical, so every difference below comes from the condition. D2 Hardened & Tempered is the stronger of the two: yield strength 1,700 MPa (247 ksi) against 460 MPa (66.7 ksi) for D2 Stress Relieved, about 3.7 times as much; tensile strength follows at 2,000 MPa (290 ksi) vs 760 MPa (110 ksi). In exchange, D2 Stress Relieved is the more ductile: elongation 14% versus 1% for D2 Hardened & Tempered, and D2 Hardened & Tempered is harder (697 HV vs 236 HV). On the shop floor, D2 Stress Relieved machines more easily (poor vs not recommended).
D2 Hardened & TemperedChoose it when strength drives the design.
D2 Stress RelievedChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
D2 Hardened & Tempered vs D2 Stress Relieved: 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.
D2 Hardened & TemperedD2 Stress Relieved
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)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 210 GPa30.5 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 7.7 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,421°C2,590 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 20 W/m·K11.6 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 10.5 µm/m·K5.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 200°C392 °F · Min Service Temperature -50°C-58 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 2.7 % IACS · Electrical Resistivity 6.5×10⁻⁷ Ω·m25.6 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.35 V · Corrosion Resistance 28 / 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 25 / 100 · Brazeability / Solderability 35 / 100 · Polishability 65 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 36 MJ/kg15,477 BTU/lb · Embodied Carbon (primary production) 3 kg CO₂/kg · Embodied Water 80 L/kg9.6 gal/lb · Typical Recycled Content 45%
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.
D2 Hardened & Tempered vs D2 Stress Relieved — frequently asked
Is D2 Hardened & Tempered stronger than D2 Stress Relieved?
Yes. D2 Hardened & Tempered has a typical yield strength of 1,700 MPa (247 ksi) against 460 MPa (66.7 ksi) for D2 Stress Relieved — about 3.7 times as much. Tensile strength is 2,000 MPa (290 ksi) vs 760 MPa (110 ksi).
Which condition does FabDigit quote by default, Hardened & Tempered or Stress Relieved?
Annealed is the default D2 condition in the FabDigit quote flow (neither Hardened & Tempered nor Stress Relieved). 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, D2 Hardened & Tempered or D2 Stress Relieved?
D2 Stress Relieved. Its machinability rates poor (30/100) against not recommended (5/100) for D2 Hardened & Tempered; for welding the order is D2 Stress Relieved first (poor, 18/100) then D2 Hardened & Tempered (not recommended, 10/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in D2 Hardened & Tempered and D2 Stress Relieved 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.