Reed Relays and
Electronics India Limited
Manufacturer of Reed Switches, Reed Sensors and Reed-based products
Reed Relays and Electronics India Limited Incorporated in 1971


AlNiCo is a type of permanent magnet which is made from an alloy of Aluminium, Nickel, Cobalt and Iron. AlNiCo magnets are suitable for Reed Switch applications that require a high service temperature as some grades of AlNiCo magnets can work up to 550C.

AlNiCo (Wikipedia)
A "horseshoe magnet" made of Alnico 5, about 1 in high. The metal bar (bottom) is a keeper. Placed across the poles when the magnet was not in use, it helped preserve the magnetization.

Alnico is a family of iron alloys which in addition to iron are composed primarily of aluminium (Al), nickel (Ni) and cobalt (Co), hence acronymal-ni-co. They also include copper, and sometimes titanium. Alnico alloys are ferromagnetic, and are used to make permanent magnets. Before the development of rare-earth magnets in the 1970s, they were the strongest type of permanent magnet. Other trade names for alloys in this family are: Alni, Alcomax, Hycomax, Columax, and Ticonal.

The composition of alnico alloys is typically 8–12% Al, 15–26% Ni, 5–24% Co, up to 6% Cu, up to 1% Ti, and the balance is Fe. The development of alnico began in 1931, when T. Mishima in Japan discovered that an alloy of iron, nickel, and aluminum had a coercivity of

400 oersteds (32 kA/m), double that of the best magnet steels of the time.

« Back to Glossary Index