Soft Magnetic Alloys

ASTM A753 Type 4 – Alloy 79

Iron13.57%Nominal Nickel80%Nominal CobaltMolybdenum5%Carbon0.03%Manganese0.95%Silicon0.42%VanadiumNiobiumPhosphorus0.02%Sulfur0.008%

Consisting of 80% Nickel, 5% Molybdenum, and the balance Iron, this alloy is used where maximum permeability and extremely high initial permeability is required, along with minimum hysteresis.

Also known as: Magnifer 79042, Carpenter HyMu 801, Hipernom1, Moly-Permalloy, Permalloy 80, Mumetal³

Applications

• Electro-magnetic shielding
• Speciale transformer laminations
• Toroidal tape wound cores
• High quality motor laminations
• Stepping motors

Type 2 – Alloy 50

Iron49%Nominal Nickel50%Nominal CobaltMolybdenumCarbon0.02%Manganese0.5%Silicon0.35%VanadiumNiobiumPhosphorusSulfur

Consisting of 49% Nickel and 51% Iron, this alloy is used where high initial permeability, maximum permeability, and low core loss is needed.

Also known as: Magnifer 502, Carpenter High Permeability 491, Alloy 4750, Supra 50³

Applications

• Transformer cores
• Highly efficient motors
• Shielding and specialised electronic devices, such as LF power transducers, chokes, relay parts, solenoids and oscillators.

ASTM A753 Type 1 – Radiometal 4550

Iron55%Ni45%

Consisting of 45% Nickel and the balance Iron, this alloy has excellent permeability with high saturation flux density.

Applications

• Sensitive relays that need to respond to very weak currents
• Transformers
• chokes and special motors where the properties of silicon-iron do not provide the required magnetic performance

ASTM A801 – Hiperco 50¹

Iron48.3%Nominal Nickel0.25%Nominal Cobalt49%Chromium0.15%Carbon0.025%Manganese0.15%Silicon0.15%Nominal Vanadium1.9%Nominal Niobium0.05%Phosphorus0.015%Sulfur0.01%

Consisting of 49% Cobalt, 49% Iron, and 2% Vanadium Hiperco 50 has the highest magnetic saturation of any commercial alloy, and greater mechanical strength than other soft magnetic alloys.

Also known as: AFK 502, VACOFLUX 50, Permendur 49, Rotelloy 3

Applications

• Electrical generators
• Pole pieces for electromagnets
• Magnetic bearings
• High magnetic flux devices and instruments

ASTM A848 Type 1 – Vim Var Core Iron

Iron99.8%Nominal Nickel0.08%Carbon0.02%Manganese0.12%Silicon0.12%Vanadium0.05%Phosphorus0.01%Sulfur0.01%

Carpenter VIM VAR Core Iron is a low carbon magnetic iron produced using vacuum induction melting and vacuum arc re-melting processes.

Other elements commonly found in low carbon irons are held as low as possible to ensure good DC magnetic properties. The double melting technique keeps the distribution of non-metallic inclusions to a minimum length and frequency so that thin wall sections will not contain leaks due to internal discontinuities.

Also known as: Carpenter Consumet Core Iron¹

Applications

• Used in components where vacuum integrity is needed, such as power tubes and microwave devices
• Relays, solenoids, magnetic pole pieces for scientific instruments

ASTM A848 Type 1 – Soft Magnetic Iron

Iron (minumum purity)99.85

This product has an Iron content of 99.85% Min, without the addition of alloy elements. All natural impurities have been largely removed.

Pure iron undergoes pacification after melting by means of vacuum degassing following solidification. It therefore has a homogenous composition with regard to distribution of the accompanying elements, a very low oxygen content, and due to the low Carbon content, the micro structure consists of pure ferrite.

This material supports excellent magnetic properties and resistance against corrosion and oxidation. It has good cold forming capabilities and is well suited to welding.

Also known as: Remko, Armco, Maximag

Applications

• Aviation construction
• Nuclear technology
• Magnet production
• Automotive construction
• Power station construction
• Gaskets in the chemical and petrochemical industries
• Magnetic shielding
• Welding rods and fuse wire
• An anti-corrosion anode

Soft Magnetic Alloy Property Comparisons