Steel 17CrS3 +AC vs 17CrS3 Case Hardened
Steel · 17CrS3 temper comparison
17CrS3 +AC and 17CrS3 Case Hardened are two conditions of the same steel grade, 17CrS3: +AC (spheroidize annealed) versus Case Hardened (carburized and hardened). The chemistry is identical, so every difference below comes from the condition. 17CrS3 Case Hardened is the stronger of the two: yield strength 560 MPa (81.2 ksi) against 310 MPa (45 ksi) for 17CrS3 +AC, about 81% more; tensile strength follows at 850 MPa (123 ksi) vs 500 MPa (72.5 ksi). In exchange, 17CrS3 +AC is the more ductile: elongation 23% versus 11% for 17CrS3 Case Hardened, and 17CrS3 Case Hardened is harder (190 HB vs 155 HB). 17CrS3 +AC runs hotter in service (300°C vs 180°C continuous). On the shop floor, 17CrS3 +AC machines more easily (good vs not recommended) and 17CrS3 +AC welds better (poor vs not recommended).
17CrS3 +ACChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
17CrS3 Case HardenedChoose it when strength drives the design.
17CrS3 +AC vs 17CrS3 Case Hardened: 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.
17CrS3 +AC17CrS3 Case Hardened
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
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 81 GPa11.7 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Compressive Strength 490 MPa71.1 ksi · Fracture Toughness (K_IC) 75 MPa·√m68.3 ksi·√in
Physical
Density and transition temperatures.
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,490°C2,714 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 44 W/m·K25.4 BTU/hr·ft·°F · Specific Heat Capacity 460 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 · Min Service Temperature -25°C-13 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 8 % IACS · Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 11 / 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: Brazeability / Solderability 60 / 100 · Polishability 45 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 1.9 kg CO₂/kg · Embodied Water 55 L/kg6.6 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.
17CrS3 +AC vs 17CrS3 Case Hardened — frequently asked
Is 17CrS3 Case Hardened stronger than 17CrS3 +AC?
Yes. 17CrS3 Case Hardened has a typical yield strength of 560 MPa (81.2 ksi) against 310 MPa (45 ksi) for 17CrS3 +AC — about 81% more. Tensile strength is 850 MPa (123 ksi) vs 500 MPa (72.5 ksi).
Which condition does FabDigit quote by default, +AC or Case Hardened?
+AC+C is the default 17CrS3 condition in the FabDigit quote flow (neither +AC nor Case Hardened). 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, 17CrS3 +AC or 17CrS3 Case Hardened?
17CrS3 +AC. Its machinability rates good (58/100) against not recommended (10/100) for 17CrS3 Case Hardened; for welding the order is 17CrS3 +AC first (poor, 33/100) then 17CrS3 Case Hardened (not recommended, 10/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 17CrS3 +AC and 17CrS3 Case Hardened 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.