Steel 17CrNiMo6-4 +A vs 17CrNiMo6-4-CH
Steel · 17CrNiMo6-4 temper comparison
17CrNiMo6-4 +A and 17CrNiMo6-4-CH are two conditions of the same steel grade, 17CrNiMo6-4: +A (annealed) versus CH (carburized and hardened). The chemistry is identical, so every difference below comes from the condition. 17CrNiMo6-4-CH is the stronger of the two: yield strength 830 MPa (120 ksi) against 400 MPa (58 ksi) for 17CrNiMo6-4 +A, about 108% more; tensile strength follows at 1,150 MPa (167 ksi) vs 650 MPa (94.3 ksi). In exchange, 17CrNiMo6-4 +A is the more ductile: elongation 18% versus 9% for 17CrNiMo6-4-CH, and 17CrNiMo6-4-CH is harder (350 HB vs 185 HB). 17CrNiMo6-4 +A runs hotter in service (200°C vs 180°C continuous). On the shop floor, 17CrNiMo6-4 +A machines more easily (good vs not recommended) and 17CrNiMo6-4 +A welds better (fair vs not recommended).
17CrNiMo6-4 +AChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
17CrNiMo6-4-CHChoose it when strength drives the design.
17CrNiMo6-4 +A vs 17CrNiMo6-4-CH: 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
Compressive Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
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 50% · Shear Strength 395 MPa57.3 ksi · Fracture Toughness (K_IC) 75 MPa·√m68.3 ksi·√in · Hardness, Rockwell B 90 HRB
Physical
Density and transition temperatures.
Same in both: Density 7.84 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °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) 11.5 µm/m·K6.4 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 7.8 % IACS · Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Corrosion Resistance 12 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Polishability
Same in both: Machinability Rating (AISI 1212 = 100 %) 60% · Formability (cold) 60 / 100 · Brazeability / Solderability 55 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 34 MJ/kg14,617 BTU/lb · Embodied Carbon (primary production) 2.3 kg CO₂/kg · Embodied Water 60 L/kg7.2 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.
17CrNiMo6-4 +A vs 17CrNiMo6-4-CH — frequently asked
Is 17CrNiMo6-4-CH stronger than 17CrNiMo6-4 +A?
Yes. 17CrNiMo6-4-CH has a typical yield strength of 830 MPa (120 ksi) against 400 MPa (58 ksi) for 17CrNiMo6-4 +A — about 108% more. Tensile strength is 1,150 MPa (167 ksi) vs 650 MPa (94.3 ksi).
Which condition does FabDigit quote by default, +A or CH?
+A is the default 17CrNiMo6-4 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, 17CrNiMo6-4 +A or 17CrNiMo6-4-CH?
17CrNiMo6-4 +A. Its machinability rates good (58/100) against not recommended (10/100) for 17CrNiMo6-4-CH; for welding the order is 17CrNiMo6-4 +A first (fair, 45/100) then 17CrNiMo6-4-CH (not recommended, 10/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 17CrNiMo6-4 +A and 17CrNiMo6-4-CH 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.