Soft Magnetic Alloys

ASTM A753 Type 4 – Alloy 79

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

Download ASTM A753 type 4 datasheet

Download ASTM A753 type 3 datasheet

Download ASTM A753 type 2 datasheet

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Type 2 – Alloy 50

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.

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ASTM A753 Type 1 – Radiometal 4550

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

Download ASTM A753 type 1 Radiometal 4550 datasheet

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ASTM A801 – Hiperco 50¹

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

Download Hiperco 50 datasheet

Download Hiperco 50A datasheet

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ASTM A848 Type 1 – Vim Var Core Iron

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

Download datasheet

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ASTM A848 Type 1 – Soft Magnetic Iron

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

Download datasheet

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Soft Magnetic Alloy Property Comparisons

Physical Properties	UNIT	ASTM A753 Type 4	ASTM AT53 Type 2	Hiperco 50	ASTM A848 Type 1 - Vim Var Core Iron
Density	lb/cu in	0.316	0.295	0.293	0.284
Specific Gravity		8.74	8.18	8.12	8.86
Curie Temp	°F	860	840	715	1400
Curie Temp	°C	460	450	380	760
Melting Point	°F	2650	2600	2600
Melting Point	°C	1454	1427	1427
Electrical Resistivity	micro-ohm-cm	59	49	41	13
Electrical Resistivity	ohm-cir mil/ft	349	290	240	78
Thermal Conductivity	W/cm °C	0.35	0.13	0.29	0.73
Thermal Conductivity	BTU-in/sq. ft-hr-°F	240	90	200	508
Specific Heat	Cal/g-°C		0.12		0.11
Specific Heat	BTU/lbm-°F		0.12		0.11
Thermal Expansion	ppm/°F (75°F to 842°F)	7.5	5.0	5.6	8.2
Thermal Expansion	ppm/°C (25°C to 450°C)	13.6	9.0	10.2	14.7

Mechanical Properties	UNIT	ASTM A753 Type 4	ASTM AT53 Type 2	Hiperco 50	ASTM A848 Type 1 - Vim Var Core Iron
Tensile Strength	ksi	98	75	118	50
Tensile Strength	MPa	676	518	814	345
Yield Strength	ksi	38	23	63	27
Yield Strength	MPa	262	159	435	190
Elongation	% in 2 in.	40	40	9	45
Typical Hardness	Rockwell	HRB 85	HRB 80	HRC 20	HRB 60
Modulus of Elasticity	Mpsi	31.4	24	30	30
Modulus of Elasticity	kMPa	217	166	207	207

Chemistry	UNIT	ASTM A753 Type 4	ASTM AT53 Type 2	Hiperco 50	ASTM A848 Type 1 - Vim Var Core Iron
Maximum % unless noted	Iron	Bal	49	49 nom.	99.8 nom.
Maximum % unless noted	Nominal Nickel	80	51	-	0.08
Maximum % unless noted	Nominal Cobalt	-	-	49 nom.	-
Maximum % unless noted	Molybdenum	5.0 nom.	-	-	-
Maximum % unless noted	Carbon	0.03	0.02	0.01	0.02
Maximum % unless noted	Manganese	0.95	0.5	-	0.12
Maximum % unless noted	Silicon	0.42	0.35	0.05	0.12
Maximum % unless noted	Vanadium	-	-	2 nom.	0.05
Maximum % unless noted	Niobium	-	-	0.05	-
Maximum % unless noted	Phosphorus	0.02	-	-	0.01
Maximum % unless noted	Sulfur	0.008	-	-	0.01