Steel FeNi42 Annealed vs FeNi42 Spring
Steel · FeNi42 temper comparison
FeNi42 Annealed and FeNi42 Spring are two conditions of the same steel grade, FeNi42: Annealed versus Spring (spring hard). The chemistry is identical, so every difference below comes from the condition. FeNi42 Spring is the stronger of the two: yield strength 880 MPa (128 ksi) against 300 MPa (43.5 ksi) for FeNi42 Annealed, about 193% more; tensile strength follows at 950 MPa (138 ksi) vs 540 MPa (78.3 ksi). In exchange, FeNi42 Annealed is the more ductile: elongation 33% versus 2% for FeNi42 Spring, and FeNi42 Spring is harder (290 HB vs 140 HB). FeNi42 Annealed runs hotter in service (350°C vs 200°C continuous). On the shop floor, FeNi42 Annealed welds better (very good vs good).
FeNi42 AnnealedChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
FeNi42 SpringChoose it when strength drives the design.
FeNi42 Annealed vs FeNi42 Spring: 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.
Elastic (Young's) Modulus
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, Vickers
Same in both: Shear Modulus 57 GPa8.3 Msi · Bulk Modulus 115 GPa16.7 Msi · Poisson's Ratio 0.29 · Hardness, Rockwell B 80 HRB
Physical
Density and transition temperatures.
Same in both: Density 8.12 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,450°C2,642 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 10.5 W/m·K6.1 BTU/hr·ft·°F · Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 5.3 µm/m·K2.9 µin/in·°F · Latent Heat of Fusion 275 J/g118 BTU/lb · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.55 V · Corrosion Resistance 30 / 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 45 / 100 · Brazeability / Solderability 80 / 100 · Polishability 70 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 100 MJ/kg42,992 BTU/lb · Embodied Carbon (primary production) 7 kg CO₂/kg · Embodied Water 190 L/kg22.8 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.
FeNi42 Annealed vs FeNi42 Spring — frequently asked
Is FeNi42 Spring stronger than FeNi42 Annealed?
Yes. FeNi42 Spring has a typical yield strength of 880 MPa (128 ksi) against 300 MPa (43.5 ksi) for FeNi42 Annealed — about 193% more. Tensile strength is 950 MPa (138 ksi) vs 540 MPa (78.3 ksi).
Which condition does FabDigit quote by default, Annealed or Spring?
Annealed is the default FeNi42 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, FeNi42 Annealed or FeNi42 Spring?
FeNi42 Spring. Its machinability rates fair (38/100) against poor (30/100) for FeNi42 Annealed; for welding the order is FeNi42 Annealed first (very good, 72/100) then FeNi42 Spring (good, 55/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in FeNi42 Annealed and FeNi42 Spring 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.