AlNiCo Magnet

AlNiCo, derived from Aluminum-Nickel-Cobalt, is a non-rare earth permanent magnetic material blending Aluminum, Nickel, Cobalt, and Iron, with traces of Titanium, Niobium, and Copper to boost coercivity through needle-phase formation. An AlNiCo magnet once ruled the permanent magnet industry, a cornerstone until rare earth magnets took precedence. Its pioneering role in advancing magnetic technology remains a landmark, even as production has waned, offering unique properties for specialized industrial and scientific applications requiring robust performance.

Despite susceptibility to demagnetization, an AlNiCo magnet shines in closed magnetic circuits or with a high length-to-diameter ratio, ensuring stable output. From loudspeakers, sensors, and guitar pickups to magnetic chucks and lifters, an AlNiCo magnet serves diverse uses. Its exceptional temperature stability makes it ideal for niche applications, delivering unmatched reliability in environments demanding consistent magnetic strength under thermal stress.

Selecting the ideal grade for an AlNiCo magnet relies on grasping its magnetic properties, critical for tailored applications. AlNiCo magnets carry trade names like Columax, Alcomax, Hycomax, and Ticonal for their grades, yet most recognize them by MMPA class names such as Alnico 2, 3, 5, 5DG, 8, 8HC, and 9, each designed for specific performance needs.

An AlNiCo magnet’s Cobalt content varies, from none in Alnico 3 to 40% in Alnico 8. Lower grades (2, 3, 4) are isotropic, lacking orientation, which results in modest magnetic output. Conversely, anisotropic grades (5, 6, 8, 9) focus magnetic strength in one direction, delivering robust performance for targeted uses, making them ideal for high-output demands.

In China’s naming system, cast AlNiCo magnets start with LNG or LNGT, followed by a number indicating minimum (BH)max in kJ/m3, with LNGT representing Aluminum, Nickel, Cobalt, and Titanium in Chinese phonetics. A “J” suffix marks high coercivity. For a sintered AlNiCo magnet, an “F” denotes sintered powder material, distinguishing its production process.