ALNICO

PERMANENT MAGNETS

ALNICO

Permanent Magnets

Developed around 1940, Alnico magnets are still used in some applications where performance stability at high temperatures is required. Alnico is the acronym that refers to a family of alloys composed mainly of aluminum (Al), nickel (Ni) and cobalt (Co), they also include iron and copper and sometimes also titanium.

The magnets can be produced both by sintering and by melting process and subsequent casting in the required shapes. The final magnetic characteristics of Alnico magnets are reached after adequate heat treatments in the presence, in the case of anisotropic magnets, of strong magnetic fields. Through particular procedures it is possible to favor a directional growth of the grains, the particles with an elongated shape have a greater coercivity along their major axis, this phenomenon is known as shape anisotropy. Due to the low coercive force, it is recommended to magnetize Alnico magnets only after assembly, to avoid accidental demagnetization.

CORROSION
RESISTENCE

Being composites mainly of aluminum, nickel and cobalt with the addition of metal elements; Alnico magnets are not subject to corrosion processes.

TEMPERATUE
RESISTENCE

The working temperature is about 500 ° C and a Curie temperature around 800 ° C. These characteristics make them the strongest magnets in extreme conditions.

MECHANICAL
RESISTANCE

The composition and the production process make it the most resistant from the mechanical point of view among the permanent magnets on the market.

LOW
COERCIVITY

It allows its use in particular fields of application, but requires that the magnetization of the product be carried out at the end of the assembly process so as not to leave the magnet with an "open magnetic circuit".

MAGNETS COMPARED IN THE HYSTERESIS CYCLE
FEATURES OF DIFFERENT MAGNETS

APPLICATIONS

LIST OF MOST DIFFUSED APPLICATIONS

MICROMOTORS

Alnico Permanent Magnet motors have characteristics with low torque values ​​and constant presumptions.

LOUDSPEAKERS

The excellent stability of Alnico magnets makes them the perfect magnets for making loudspeaker systems.

RELE’ EMR

The Pick Up function is necessary for lifting thin sheets from a pack of sheets. At the same time, the Pick Up function makes the safety factor visible.

GUITAR PICK-UP

For pick-ups generally Alnico 2, 3, 4 and 5 are used. In a rather general way the variation of the sound goes from an Alnico 2 pick-up, characterized by a certain softness of the attack on the bass, to an Alnico 5 which shows greater aggressiveness.

ELECTROPERMANENT CHUCKS

The alnico is still strongly used especially in the field of permanent-electro systems due to its special characteristic of a very low coercive field that allows demagnetization and magnetization with low electric power applications.

ELECTROPERMANENT LIFTING SYSTEMS

The alnico is still strongly used especially in the field of permanent-electro systems due to its special characteristic of a very low coercive field that allows demagnetization and magnetization with low electric power applications.

FAQs

TECHNICAL AND OPERATING INFORMATIONS

Differences between cast and sintered alnico

The Alnico obtained by fusion can be made with different shapes. The initial investment is expensive due to the necessary construction of the mold.
The sintered Alnico is usually made in small dimensions and allows closer tolerances, even if the magnetic properties will be slightly worse than the melted one, it will have a better mechanical resistance.

Why are Alnico magnets anisotropic?

The final magnetic characteristics of alnico magnets are obtained after particular thermal treatments in the presence of strong magnetic fields. The effect of these fields is to direct the material in the required direction, enhancing the magnetic characteristics. The alnico magnets are usually anisotropic as the directions of magnetization are established a priori - they are therefore called anisotropic or oriented.

Why are Alnico magnets red?

Despite having a corrosion-resistant behavior, Alnico magentas often have a coating consisting of a red-colored coating, this is done because their appearance is gray and uneven, Red paint is usually used to characterize them, especially in the sector of sealing magnets. They can be coated as per customer request, chrome or nickel plated.