0.5mm Thickness Precision Alloys Hard Strip 20% Elongation For Magnetic Head
(Common Name: Ni79Mo4, E11c, malloy, permalloy, 79HM)
Ohmalloy-1J79 is a nickel-iron magnetic alloy, with about 80% nickel and 20% iron content. Invented in 1914 by physicist Gustav Elmen at Bell Telephone Laboratories, it is notable for its very high magnetic permeability, which makes it useful as a magnetic core material in electrical and electronic equipment, and also in magnetic shielding to block magnetic fields. Commercial permalloy alloys typically have relative permeability of around 100,000, compared to several thousand for ordinary steel.
In addition to high permeability, its other magnetic properties are low coercivity, near zero magnetostriction, and significant anisotropic magnetoresistance. The low magnetostriction is critical for industrial applications, allowing it to be used in thin films where variable stresses would otherwise cause a ruinously large variation in magnetic properties. Permalloy's electrical resistivity can vary as much as 5% depending on the strength and the direction of an applied magnetic field. Permalloys typically have the face centered cubic crystal structure with a lattice constant of approximately 0.355 nm in the vicinity of a nickel concentration of 80%. A disadvantage of permalloy is that it is not very ductile or workable, so applications requiring elaborate shapes, such as magnetic shields, are made of other high permeability alloys such as mu metal. Permalloy is used in transformer laminations and magnetic recording heads.
Ohmalloy-1J79 widely used in radio-electronic industry, precision instruments, remote control and automatic control system.
Ohmalloy 1J79 / Permalloy strip for magnetic head
Normal composition%
| Ni |
78.5~80.0 |
Fe |
Bal. |
Mn |
0.6~1.1 |
Si |
0.3~0.5 |
| Mo |
3.8~4.1 |
Cu |
≤0.2 |
|
|
|
|
| C |
≤0.03 |
P |
≤0.02 |
S |
≤0.02 |
|
|
Typical Physical properties
| Density (g/cm3) |
8.6 |
| Electrical resistivity at 20ºC(OMmm2/m) |
0.55 |
| Coefficient of linear expansion(20ºC~200ºC)X10-6/ºC |
10.3~11.5 |
| Saturation magnetostriction coefficient λθ/ 10-6 |
2.0 |
| Curie point Tc/ ºC |
450 |
Typical Mechanical properties
| Yield strength |
Tensile Strength |
Elongation |
| Mpa |
Mpa |
% |
| 980 |
1030 |
3~50 |
The magnetic properties of alloys with high permeability in weak fields |
| 1J79 |
Initial permeability |
Maximum permeability |
Coercivity |
Saturation magnetic induction intensity |
Сold-rolled strip/ sheet.
Thickness, mm |
μ0.08/ (mH/m) |
μm/ (mH/m) |
Hc/ (A/m) |
BS/ T |
| ≥ |
≤ |
| 0.01 mm |
17.5 |
87.5 |
5.6 |
0.75 |
| 0.1~0.19 mm |
25.0 |
162.5 |
2.4 |
| 0.2~0.34 mm |
28.0 |
225.0 |
1.6 |
| 0.35~1.0 mm |
30.0 |
250.0 |
1.6 |
| 1.1~2.5 mm |
27.5 |
225.0 |
1.6 |
| 2.6~3.0 mm |
26.3 |
187.5 |
2.0 |
| cold drawn wire |
|
| 0.1 mm |
6.3 |
50 |
6.4 |
| Bar |
|
| 8-100 mm |
25 |
100 |
3.2 |
| |
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|
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|
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| Heat treatment 1J79 |
| Annealing media |
Vacuum with a residual pressure not higher than 0.1Pa, hydrogen with a dew point of not higher than minus 40 ºC. |
| The heating temperature and rate |
1100~1150ºC |
| Holding time |
3~6 |
| Cooling rate |
With 100 ~ 200 ºC/ h cooled to 600 ºC, rapidly cooled to 300ºC |
Style of supply
| Alloys Name |
Type |
Dimension |
|
| OhmAlloy-1J79 |
Wire |
D= 0.1~8mm |
|
| OhmAlloy-1J79 |
Strip |
W= 8~390mm |
T= 0.3mm |
| OhmAlloy-1J79 |
Foil |
W= 10~100mm |
T= 0.01~0.1mm |
| OhmAlloy-1J79 |
Bar |
Dia= 8~100mm |
L= 50~1000mm |
FAQ
1. What's the minimum quantity customer can order?
If we have your size in stock, we can provide any quantity you want.
If we do not have, for spool wire, we can produce 1 spool, about 2-3kg. For coil wire, 25kg.
2. How can you pay for small sample amount?
We have Western union account, wire transfer for sample amount also ok.
3. Customer do not have express account. How will us arrange the delivery for sample order?
Just need to provide your address information, we will check the express cost, you can arrange the express cost together with sample value.
4. What's our payment terms?
We can accept LC T/T payment terms, it also depending on delivery and total amount. Let's talk more in details after getting your detailed requirements.
5. Do you provide free samples?
If you want several meters and we have stock of your size, we can provide, customer need to bear the International express cost.
6. What's our working time?
We will give you reply through email/phone Online contact tool within 24 hours. No matter working day or holidays.
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