Alnico Magnet

Short Description:

Alnico magnet is a type of hard magnet mainly composed of alloys of Aluminum, Nickel, and Cobalt. It is manufactured through either casting or sintering process. Before rare earth magnets were developed in 1970, Alnico magnet was the strongest type of permanent magnet and widely used.


Product Detail

Product Tags

Nowadays, in many applications Alnico has been replaced by Neodymium or Samarium Cobalt magnet. However, its property like temperature stability and very working high temperatures makes Alnico magnets indispensable in certain application markets.

Advantages

1. High magnetic field. Residual induction is high to 11000 Gauss almost similar to Sm2Co17 magnet, and then it can produce high magnetic field around.

2. High working temperature. Its maximum working temperature can be high to 550⁰C.

3. High temperature stability: Alnico magnets have the best temperature coefficients of any magnet material. Alnico magnets should be regarded as the best choice in extremely high temperature applications.

4. Excellent corrosion resistance. Alnico magnets are not prone to corrosion and can normally be used without any surface protection

Disadvantages

1. Easy to demagnetize: Its maximum low coercive force Hcb is lower than 2 kOe and then it is easy to demagnetize in some low demagnetizing field, even not handled with care.

2. Hard and brittle. It is prone to chipping and cracking.

Factors to Consider for Applications

1. As the coercivity of Alnico magnets is low, the ratio of length to diameter should be 5:1 or larger so as to get a good work point of Alnico.

2. As Alnico magnets are easily demagnetized by careless handling, it is recommended to make the magnetizing after assembly.

3. Alnico magnets offer outstanding temperature stability. The output from Alnico magnets varies the least with changes in temperature, making it an ideal choice for temperature sensitive applications, such as medical and military.

Why Choose Horizon Magnetics as Alnico Magnet Supplier

Definitely we are not an Alnico magnet manufacturer, but we are an expert in magnetic types of permanent magnets including Alnico. Moreover, our own produced rare earth magnets and magnetic assemblies will enable customers to have a one-stop purchase of magnet products from us conveniently.

Typical Magnetic Properties

Cast / Sintered Grade Equivalent MMPA Br Hcb (BH)max Density α(Br) TC TW
mT KA/m KJ/m3 g/cm3 %/ºC ºC ºC
Cast LNG37 Alnico5 1200 48 37 7.3  -0.02 850 550
LNG40 1230 48 40 7.3  -0.02 850 550
LNG44 1250 52 44 7.3  -0.02 850 550
LNG52 Alnico5DG 1300 56 52 7.3  -0.02 850 550
LNG60 Alnico5-7 1330 60 60 7.3  -0.02 850 550
LNGT28 Alnico6 1000 56 28 7.3  -0.02 850 550
LNGT36J Alnico8HC 700 140 36 7.3  -0.02 850 550
LNGT18 Alnico8  580 80 18 7.3  -0.02 850 550
LNGT38 800 110 38 7.3  -0.02 850 550
LNGT44 850 115 44 7.3  -0.02 850 550
LNGT60 Alnico9 900 110 60 7.3  -0.02 850 550
LNGT72 1050 112 72 7.3  -0.02 850 550
Sintered SLNGT18 Alnico7 600 90 18 7.0  -0.02 850 450
SLNG34 Alnico5 1200 48 34 7.0  -0.02 850 450
SLNGT28 Alnico6 1050 56 28 7.0  -0.02 850 450
SLNGT38 Alnico8 800 110 38 7.0  -0.02 850 450
SLNGT42 850 120 42 7.0  -0.02 850 450
SLNGT33J Alnico8HC 700 140 33 7.0  -0.02 850 450

Physical Properties for Alnico Magnet

Characteristics Reversible Temperature Coefficient, α(Br)  Reversible Temperature Coefficient, β(Hcj) Curie Temperature Max Operating Temperature Density Hardness, Vickers  Electrical Resistivity Coefficient of Thermal Expansion Tensile Strength Compression Strength
Unit %/ºC %/ºC ºC ºC g/cm3 Hv μΩ • m 10-6/ºC Mpa Mpa
Value -0.02 -0.03~+0.03 750-850 450 or 550 6.8-7.3 520-700 0.45~0.55 11~12 80~300 300~400

  • Previous:
  • Next: