1J85
1J85 is a nickel–iron magnetic alloy, with about 80% nickel and 20% iron content. It is notable for its very high magnetic permeability, making it useful as a magnetic core material in electrical and electronic equipment and in magnetic shielding to block magnetic fields.Commercial perm-alloy alloys typically have a relative permeability of around 100,000, compared to several thousand for ordinary steel.
1J85 is a nickel–iron magnetic alloy, with about 80% nickel and 20% iron content. It is notable for its very high magnetic permeability, making it useful as a magnetic core material in electrical and electronic equipment and in magnetic shielding to block magnetic fields.Commercial perm-alloy alloys typically have a 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 an-isotropic magneto resistance.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. Perm-alloys typically have a face-centered cubic crystal structure with a lattice constant of approximately 0.355nm near a nickel concentration of 80%.
A disadvantage of perm-alloy is that it is not very pliable 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.
Physical properties:
Density: 8.75 g/cm3
Curie point (°C): 400;
Resistivity (μΩ.m): 0.56;
Saturation magnetostriction (×10-6): 0.5
Extreme chemical composition:
Fe：Balance
Mo：4.8-5.2
Ni：79-81
Cu：0.2max
Mn：0.3-0.6
Si：0.15-0.3
C：0.03max
S：0.02
P：0.02
AC magnetic properties:
1J85 |
Product |
Grade |
Thickness/ mm | When the peak magnetic field intensity is 0.1A/m, the elastic permeability at different frequencies is μ1. | |||
60Hz | 400Hz | 1kHz | 10kHz | ||||
mH/m | |||||||
≥ | |||||||
Cold rolled strip | II | 0.02 | 20 | 15 | |||
0.05 | 31.3 | 11.3 | |||||
0.1 | 31.3 | 25 | |||||
0.2 | 23.8 | 10 | |||||
0.35 | 38 | 12.5 | |||||
DC magnetic properties:
1J85 |
Product |
Level |
thickness or diameter/mm | Magnetic permeability under magnetic field strength of 0.08A/m μ0.08 | Maximum magnetic permeability/μm | Coercivity/Hc | Saturation magnetic induction intensity/Bs |
mH/m | A/m | T | |||||
≥ | ≤ | ≥ | |||||
cold rolled strip |
I | 0.005~0.01 | 20 | 87.5 | 4.8 | 0.7 | |
0.02~0.04 | 22.5 | 100 | 3.6 | 0.7 | |||
0.05～0.09 | 35 | 137.5 | 2.4 | 0.7 | |||
0.1～0.19 | 37.5 | 187.5 | 1.6 | 0.7 | |||
0.2~0.34 | 50 | 225 | 1.2 | 0.7 | |||
0.35~1 | 62.5 | 312.5 | 0.8 | 0.7 | |||
1.1~2 | 50 | 187.5 | 1.2 | 0.7 | |||
2.1~3 | 43.8 | 150 | 1.4 | 0.7 | |||
Ⅱ | 0.02~0.04 | 37.5 | 137.5 | 2.4 | 0.7 | ||
0.05~0.09 | 50 | 175 | 1.6 | 0.7 | |||
0.1~0.19 | 62.5 | 225 | 1.2 | 0.7 | |||
0.2~0.34 | 75 | 250 | 1 | 0.7 | |||
0.35 | 75 | 325 | 0.7 | 0.7 | |||
cold rolled plate | 0.5~1 | 56.2 | 275 | 0.9 | 0.7 | ||
1.1～2 | 45 | 175 | 1.3 | 0.7 | |||
Hot rolled (forged) flat products | 3~30 | 37.5 | 125 | 1.6 | 0.7 | ||
Hot rolled (forged) bars | 8~120 | 37.5 | 125 | 1.6 | 0.7 | ||
characteristic:
1J85 alloy has high initial magnetic permeability and low coercive force.
Applications:
1J85 is widely used in radio-electronic industry, precision instruments, remote control and automatic control system.
1J85 alloy is used to make various transformer cores, transformers, magnetic amplifiers, choke cores and magnetic shields that work in weak magnetic fields
form:
Strip, foil, sheet, tube, rod