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Steel FeNi42 vs GX3Ni36

Steel · grade comparison

Steel FeNi42 and GX3Ni36 are both steel grades. FeNi42 is the stronger of the two: yield strength 300 MPa (43.5 ksi) against 240 MPa (34.8 ksi) for GX3Ni36, about 25% more; tensile strength follows at 540 MPa (78.3 ksi) vs 450 MPa (65.3 ksi). FeNi42 is the more ductile: elongation 33% versus 25% for GX3Ni36, and FeNi42 is harder (140 HB vs 130 HB). FeNi42 runs hotter in service (350°C vs 200°C continuous) and FeNi42 conducts electricity better (2.5 % IACS vs 2.1 % IACS). On the shop floor, FeNi42 welds better (very good vs good).

FeNi42Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

FeNi42 vs GX3Ni36: properties

FeNi42GX3Ni36

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

145 GPa21 Msi
140 GPa20.3 Msi

Shear Modulus

57 GPa8.3 Msi
55 GPa8 Msi

Bulk Modulus

115 GPa16.7 Msi
105 GPa15.2 Msi

Tensile Strength (Ultimate)

540 MPa78.3 ksi
450 MPa65.3 ksi

Yield Strength (0.2% offset)

300 MPa43.5 ksi
240 MPa34.8 ksi

Elongation at Break

33%
25%

Reduction in Area

65%
33%

Shear Strength

370 MPa53.7 ksi
320 MPa46.4 ksi

Fatigue Strength (Endurance Limit)

260 MPa37.7 ksi
195 MPa28.3 ksi

Charpy V-Notch Impact (RT)

150 J111 ft·lbf
60 J44.3 ft·lbf

Hardness, Brinell

140 HB
130 HB

Hardness, Rockwell B

80 HRB
73 HRB

Hardness, Vickers

150 HV
137 HV

Compressive Strength

—
245 MPa35.5 ksi

Fracture Toughness (K_IC)

—
75 MPa·√m68.3 ksi·√in

Same in both: Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Density

8.12 g/cm³0.29 lb/in³
8.1 g/cm³0.29 lb/in³

Same in both: 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.

Thermal Conductivity

10.5 W/m·K6.1 BTU/hr·ft·°F
11 W/m·K6.4 BTU/hr·ft·°F

Specific Heat Capacity

500 J/kg·K0.12 BTU/lb·°F
515 J/kg·K0.12 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

5.3 µm/m·K2.9 µin/in·°F
2.2 µm/m·K1.2 µin/in·°F

Max Service Temperature (continuous)

350°C662 °F
200°C392 °F

Same in both: Latent Heat of Fusion 275 J/g118 BTU/lb · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.5 % IACS
2.1 % IACS

Electrical Resistivity

7×10⁻⁷ Ω·m27.6 µΩ·in
8.2×10⁻⁷ Ω·m32.3 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.55 V
-0.35 V

Corrosion Resistance

30 / 100
25 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability Rating (AISI 1212 = 100 %)

28%
25%

Weldability

72 / 100
58 / 100

Formability (cold)

85 / 100
20 / 100

Castability

45 / 100
50 / 100

Brazeability / Solderability

80 / 100
65 / 100

Same in both: Machinability 30 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

100 MJ/kg42,992 BTU/lb
90 MJ/kg38,693 BTU/lb

Embodied Water

190 L/kg22.8 gal/lb
200 L/kg24 gal/lb

Typical Recycled Content

30%
45%

Same in both: Embodied Carbon (primary production) 7 kg CO₂/kg

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

67 kN·m/kg
56 kN·m/kg

Specific Stiffness (E / density)

17.9 MN·m/kg
17.3 MN·m/kg

Modulus of Resilience

310 kJ/m³
206 kJ/m³

Thermal Shock Resistance Index

7
16

Same in both: Thermal Diffusivity 2.6 mm²/s

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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scaleGX3Ni36FeNi42

Manufacturing and finishing

CapabilityFeNi42GX3Ni36
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

Both take the same 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

FeNi42 vs GX3Ni36 — frequently asked

Is FeNi42 stronger than GX3Ni36?

Yes. FeNi42 has a typical yield strength of 300 MPa (43.5 ksi) against 240 MPa (34.8 ksi) for GX3Ni36 — about 25% more. Tensile strength is 540 MPa (78.3 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, FeNi42 or GX3Ni36?

Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which welds better, FeNi42 or GX3Ni36?

FeNi42. Its weldability rates very good (72/100) against good (58/100) for GX3Ni36.

Ready to make it?

Upload a CAD file and FabDigit prices the part in FeNi42 and GX3Ni36 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.