AlNiCo is the abbreviation of Aluminum-Nickel-Cobalt. As a member of non-rare earth metallic permanent magnetic material, AlNiCo magnet was developed by Japanese metallurgy Tokushichi Mishima in 1931 and once ruled the permanent magnet industry before the rare earth permanent magnet was emerged. AlNiCo is composed of primary Aluminum, Nickel, Cobalt, and Iron. Furthermore, minor amount of alloying element Titanium, Niobium, and Copper is added to matrix phase to promote the growth of needle phase and thereby enhance coercivity. Besides commonly used areas like loudspeaker, sensor, guitar pickup, magnetic chuck, or magnetic lifter, AlNiCo is still serving for some specialty application owing to its matchless temperature stability.
Cast AlNiCo Magnet vs. Sintered AlNiCo Magnet
AlNiCo can be made by either casting or sintering processes. AlNiCo grades mainly vary in Cobalt content and relevant heat treatment process. This historical permanent magnet can be further divided to isotropic or anisotropic and grain oriented or grain non-oriented. Cast magnet is larger in density which provides it better magnetic performance. Casting process also well-suited to large and complex shapes. Sintered magnet exhibit slighter lower magnetic performance but better mechanical properties.
| Material |
Max. Energy Product (BH)max |
Curie Temperature Tc |
Coefficient of Thermal Expansion | Electrical Resistivity | Density | Hardness | Tensile Modules |
| MGOe | ℃ | 10-6/℃ | μΩ·m | g/cm3 | HRC | kN/mm2 | |
| Cast AlNiCo Magnet | 1.00-5.25 | 760-860 | 11.0-13.0 | 45-75 | 6.9-7.3 | 45-55 | 0.02-0.15 |
| Sintered AlNiCo Magnet | 1.00-12.00 | 810-860 | 11.0-12.4 | 50-70 | 6.8-7.0 | 45 | 0.35-0.45 |
Shape Categories of AlNiCo Magnet
Influencing Factors of AlNiCo Magnet Price
AlNiCo magnet price is still one of the most concerned factors to users even its market share and cost are relatively low. Cobalt and Nickel content in AlNiCo ranges from 0-42wt% and 13-28wt%, respectively. This means that Cobalt price trend and Nickel price trend have the most significantly impact on the AlNiCo magnet price. The majority of AlNiCo magnet are manufactured via casting process in terms of the annual yield. Besides high performance magnet like AlNiCo 8 or AlNiCo 9, most of cast magnets utilize recycled Cobalt and Nickel as raw material, thus have limited demand for primary Cobalt and Nickel. Price trends of these two recycled material can basically refer to primary material’s tendencies.