Technical Data Sheet
| Chemical Composition Limits | |||||||
| Weight% | C | Mn | Si | P | S | Ni | Fe |
| Nickel Iron 4750 | 0.035 max | 0.8 max | 0.5 max | 0.02 max | 0.008 max | 47.0-50.0 | Bal |
| As per MIL-N-14411 Comp 3 and 4 |
Alloy 4750/ High Perm 49® is a 48% nickel-iron alloy which combines a high saturation flux density (approx. 16000 gauss / 1.6 tesla) with high magnetic permeability and low core loss. This alloy has the high saturation flux density of any of the nickel-iron alloys, making it a versatile alloy. Typical applications include laminated cores for instrument transformers, magnetic shields, and cores for certain electronic and communications devices where its high permeability at low magnetizing forces can greatly increase the device\’s efficiency.
In order to achieve the maximum softness and optimum magnetic and electrical properties, Alloy 4750 should be annealed in a dry hydrogen atmosphere at 2150°F for 2-4 hours, followed by a furnace cool at 100-200°F per hour down to 800°F and at any rate thereafter.
Typical Mechanical Properties
| Material | Condition | Tensile Strength | Modus of Elasticity (in tension) | Elongation (%) | Hardness Rb | ||
| ksi | Mpa | psi x10 (4) | Mpa x 10 (3) | ||||
| Alloy 4750 Sheet | As cold drawn | 130 | 896 | 24 | 166 | 5 | 100 |
| Alloy 4750 Sheet | Forming/Deep Drwg | 80 | 552 | 24 | 166 | 32 | 68 |
| Material | Condition | Tensile Strength | Yield Strength | Elongation (%) | Reduction of area (%) | Hardness Rb | ||
| ksi | Mpa | ksi | Mpa | |||||
| Alloy 4750 Bar | As cold drawn | 95 | 655 | 80 | 552 | 25 | 62 | 98 |
| Alloy 4750 Bar | Hydrogen (2150°F) | 70 | 483 | 22 | 152 | 45 | 68 | 62 |
| Alloy 4750 Bar | Hydrogen (1600°F) | 75 | 517 | 23 | 154 | 43 | 65 | 75 |
Technical Data
Physical Properties
Specific Gravity – 8.18
Density – 0.2950 lb/in
³
Mean Specific Heat – 0.1200 Btu/lb/°F
Thermal Conductivity – 90.20 BTU-in/hr/ft
²/°F
Modulus of Elasticity
After Process Anneal at 871°C, in tension, Bar – 22.0 x 10³ ksi
After Process Anneal at 871 °C, in torsion, Bar – 7.60 x 10³ ksi
Cold drawn, in torsion, Bar – 7.80 x 10³ ksi
Cold drawn, in tension, Bar – 24.0 x 10³ ksi
Cold rolled, in tension, Strip – 24.0 x 10³ ksi
Forming and Deep Draw Qlty, in tension, Strip – 24.0 x 10³ ksi
Hydrongen Annealed @ 1177°C, in tension, Bar – 22.5 x 10³ ksi
Hydrongen Annealed @ 1177°C, in torsion, Bar – 7.50 x 10³ ksi
Electrical Resistivity – 290.0 ohm-cir-mil/ft
Temp Coefficient of Electrical Resistance – 20.0 x 10(-4) Ohm/Ohm/
°F
Curie Temperature – 840 to 930°F
Melting Range – 2600°F
Magnetic Properties
DC Magnetic Properties (according to ASTM A-596)
| Properties | Bar | Strip | |
| 0.014" | 0.025-0.125" | ||
| Initial Permeability (B100) | 6500 | 12000 | 8000 |
| Max. Permeability | 75000 | 150000 | 90000 |
| Residual Magnetism (Gausses | 9000 | 9000 | 9000 |
| Coercive Force, Oersteds from 10,000 Gausses | 0.04/0.07 | 0.05-0.06 | 0.004-0.007 |
| Saturation Induction from H-100 Oersteds, Gausses | 15000 | 15000 | 15000 |
Remant Flux & Coercive Force
0.060" thick rings from a flux density of 13,000 gausses
| Treatment | Remnant Flux Gausse | Coercive Force Oersteds |
| Typical Mill Process Anneal | 6300 | 0.85 |
| 1450°F-2h-Dry H2 | 9900 | 0.48 |
| 1600°F-2h-Dry H2 | 10200 | 0.32 |
| 17500°F-2h-Dry H2 | 10300 | 0.18 |
| 2050°F-2h-Dry H2 | 10900 | 0.05 |
Availability
Alloy 4750 is available in bar, wire, sheet and strip. For all stock availability contact Sales for further availability.
Specifications
UNS K94840
Carpenter High Perm 49®
AMS 7718
Mil-N-14411 Comp 3 – all products forms
Mil-N-14411 Comp 4 – strip (<0.020" thick)
ASTM A753 Alloy 2
IEC 404-8-6 (Alloy class E3)