Type 1 (K94490) Iron-Nickel Soft Magnetic Alloy
Type 1 magnetic alloy is an otherwise-unclassified alloy of iron. It has a very high density among iron alloys. In addition, it has a very low heat capacity and a very high base cost.
The properties of Type 1 magnetic alloy include two common variations. This page shows summary ranges across both of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare Type 1 magnetic alloy to: otherwise unclassified iron alloys (top), all iron alloys (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Elastic (Young's, Tensile) Modulus
190 GPa 27 x 106 psi
Elongation at Break
4.0 to 38 %
Poisson's Ratio
0.3
Shear Modulus
72 GPa 10 x 106 psi
Tensile Strength: Ultimate (UTS)
500 to 830 MPa 73 to 120 x 103 psi
Tensile Strength: Yield (Proof)
220 to 790 MPa 32 to 120 x 103 psi
Thermal Properties
Curie Temperature
440 °C 820 °F
Latent Heat of Fusion
270 J/g
Melting Completion (Liquidus)
1420 °C 2590 °F
Melting Onset (Solidus)
1370 °C 2500 °F
Specific Heat Capacity
460 J/kg-K 0.11 BTU/lb-°F
Thermal Expansion
12 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
3.1 % IACS
Electrical Conductivity: Equal Weight (Specific)
3.4 % IACS
Otherwise Unclassified Properties
Base Metal Price
31 % relative
Density
8.3 g/cm3 520 lb/ft3
Embodied Carbon
5.6 kg CO2/kg material
Embodied Energy
77 MJ/kg 33 x 103 BTU/lb
Embodied Water
130 L/kg 16 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
33 to 150 MJ/m3
Resilience: Unit (Modulus of Resilience)
130 to 1690 kJ/m3
Stiffness to Weight: Axial
12 points
Stiffness to Weight: Bending
23 points
Strength to Weight: Axial
17 to 28 points
Strength to Weight: Bending
17 to 24 points
Thermal Shock Resistance
16 to 26 points
Alloy Composition
| Fe | 50.7 to 56.5 | |
| Ni | 43.5 to 46.5 | |
| Mn | 0 to 0.8 | |
| Si | 0 to 0.5 | |
| Co | 0 to 0.5 | |
| Cr | 0 to 0.3 | |
| Mo | 0 to 0.3 | |
| Cu | 0 to 0.3 | |
| C | 0 to 0.050 | |
| S | 0 to 0.030 | |
| P | 0 to 0.010 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM A753: Standard Specification for Wrought Nickel-Iron Soft Magnetic Alloys (UNS K94490, K94840, N14076, N14080)
Properties and Selection: Irons, Steels and High Performance Alloys, ASM Handbook vol. 1, ASM International, 1993
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015