Steel SKD11 Annealed vs SKD11 H&T 55-58 HRC
Steel · SKD11 temper comparison
SKD11 Annealed and SKD11 H&T 55-58 HRC are two conditions of the same steel grade, SKD11: Annealed versus H&T 55-58 HRC (higher temper (300–500 °C) for tougher tooling). The chemistry is identical, so every difference below comes from the condition. SKD11 H&T 55-58 HRC is the stronger of the two: yield strength 1,600 MPa (232 ksi) against 500 MPa (72.5 ksi) for SKD11 Annealed, about 3.2 times as much; tensile strength follows at 1,800 MPa (261 ksi) vs 820 MPa (119 ksi). In exchange, SKD11 Annealed is the more ductile: elongation 12% versus 2% for SKD11 H&T 55-58 HRC, and SKD11 H&T 55-58 HRC is harder (57 HRC vs 20 HRC). SKD11 H&T 55-58 HRC runs hotter in service (400°C vs 250°C continuous). On the shop floor, SKD11 Annealed machines more easily (poor vs not recommended).
SKD11 AnnealedChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
SKD11 H&T 55-58 HRCChoose it when strength drives the design, or when the part sees heat.
SKD11 Annealed vs SKD11 H&T 55-58 HRC: 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.
SKD11 AnnealedSKD11 H&T 55-58 HRC
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Rockwell C
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 · Reduction in Area 20% · Shear Strength 550 MPa79.8 ksi · Fatigue Strength (Endurance Limit) 380 MPa55.1 ksi · Hardness, Brinell 225 HB · Hardness, Rockwell B 98 HRB
Physical
Density and transition temperatures.
Same in both: Density 7.7 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,250°C2,282 °F · Liquidus Temperature 1,420°C2,588 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
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) 10.9 µm/m·K6.1 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -30°C-22 °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 25 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Same in both: Machinability Rating (AISI 1212 = 100 %) 30% · Weldability 20 / 100 · Formability (cold) 25 / 100 · Castability 25 / 100 · Brazeability / Solderability 40 / 100 · Polishability 80 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 36 MJ/kg15,477 BTU/lb · Embodied Carbon (primary production) 2.6 kg CO₂/kg · Embodied Water 70 L/kg8.4 gal/lb · Typical Recycled Content 40%
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.
SKD11 Annealed vs SKD11 H&T 55-58 HRC — frequently asked
Is SKD11 H&T 55-58 HRC stronger than SKD11 Annealed?
Yes. SKD11 H&T 55-58 HRC has a typical yield strength of 1,600 MPa (232 ksi) against 500 MPa (72.5 ksi) for SKD11 Annealed — about 3.2 times as much. Tensile strength is 1,800 MPa (261 ksi) vs 820 MPa (119 ksi).
Which condition does FabDigit quote by default, Annealed or H&T 55-58 HRC?
Annealed is the default SKD11 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, SKD11 Annealed or SKD11 H&T 55-58 HRC?
SKD11 Annealed. Its machinability rates poor (32/100) against not recommended (10/100) for SKD11 H&T 55-58 HRC.
Ready to make it?
Upload a CAD file and FabDigit prices the part in SKD11 Annealed and SKD11 H&T 55-58 HRC 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.