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Steel 1J34 vs Supermalloy

Steel · grade comparison

Steel 1J34 and Supermalloy are both steel grades. 1J34 is the stronger of the two: yield strength 260 MPa (37.7 ksi) against 230 MPa (33.4 ksi) for Supermalloy, about 13% more. In exchange, Supermalloy is the more ductile: elongation 40% versus 30% for 1J34, and 1J34 is harder (130 HB vs 115 HB). 1J34 is lighter (8.2 g/cm³ vs 8.77 g/cm³ for Supermalloy) and Supermalloy is stiffer (210 GPa vs 185 GPa).

1J34Choose it when strength drives the design, or when weight is the constraint.

SupermalloyChoose it when the part is bent, formed or impact-loaded.

1J34 vs Supermalloy: properties

1J34Supermalloy

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

185 GPa26.8 Msi
210 GPa30.5 Msi

Shear Modulus

71 GPa10.3 Msi
80 GPa11.6 Msi

Bulk Modulus

160 GPa23.2 Msi
175 GPa25.4 Msi

Poisson's Ratio

0.3
0.31

Yield Strength (0.2% offset)

260 MPa37.7 ksi
230 MPa33.4 ksi

Elongation at Break

30%
40%

Reduction in Area

55%
70%

Compressive Strength

265 MPa38.4 ksi
—

Shear Strength

380 MPa55.1 ksi
360 MPa52.2 ksi

Charpy V-Notch Impact (RT)

90 J66.4 ft·lbf
180 J133 ft·lbf

Hardness, Brinell

130 HB
115 HB

Hardness, Rockwell B

74 HRB
65 HRB

Hardness, Vickers

140 HV
120 HV

Same in both: Tensile Strength (Ultimate) 560 MPa81.2 ksi · Fatigue Strength (Endurance Limit) 250 MPa36.3 ksi

Physical

Density and transition temperatures.

Density

8.2 g/cm³0.3 lb/in³
8.77 g/cm³0.32 lb/in³

Melting Point (Solidus)

1,440°C2,624 °F
1,400°C2,552 °F

Liquidus Temperature

1,470°C2,678 °F
1,450°C2,642 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

14 W/m·K8.1 BTU/hr·ft·°F
19 W/m·K11 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

10 µm/m·K5.6 µin/in·°F
12.5 µm/m·K6.9 µin/in·°F

Latent Heat of Fusion

275 J/g118 BTU/lb
290 J/g125 BTU/lb

Min Service Temperature

-60°C-76 °F
-196°C-321 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Max Service Temperature (continuous) 400°C752 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

3.8 % IACS
2.9 % IACS

Electrical Resistivity

4.5×10⁻⁷ Ω·m17.7 µΩ·in
6×10⁻⁷ Ω·m23.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.4 V
-0.2 V

Corrosion Resistance

25 / 100
45 / 100

Manufacturability

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

Machinability

30 / 100
28 / 100

Weldability

55 / 100
60 / 100

Formability (cold)

70 / 100
85 / 100

Castability

45 / 100
40 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 25% · Brazeability / Solderability 65 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

130 MJ/kg55,890 BTU/lb
135 MJ/kg58,040 BTU/lb

Embodied Carbon (primary production)

11 kg CO₂/kg
10.5 kg CO₂/kg

Embodied Water

220 L/kg26.4 gal/lb
200 L/kg24 gal/lb

Same in both: Typical Recycled Content 25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

68 kN·m/kg
64 kN·m/kg

Specific Stiffness (E / density)

22.6 MN·m/kg
23.9 MN·m/kg

Modulus of Resilience

183 kJ/m³
126 kJ/m³

Thermal Diffusivity

3.7 mm²/s
4.7 mm²/s

Same in both: Thermal Shock Resistance Index 4

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 scaleSupermalloy1J34

Manufacturing and finishing

Capability1J34Supermalloy
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.

1J34 vs Supermalloy — frequently asked

Is 1J34 stronger than Supermalloy?

Yes. 1J34 has a typical yield strength of 260 MPa (37.7 ksi) against 230 MPa (33.4 ksi) for Supermalloy — about 13% more. Tensile strength is 560 MPa (81.2 ksi) vs 560 MPa (81.2 ksi).

Which is cheaper, 1J34 or Supermalloy?

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, 1J34 or Supermalloy?

Supermalloy. Its weldability rates good (60/100) against good (55/100) for 1J34.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 1J34 and Supermalloy 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.