What is the reason for not using alnico in electromagnet?
Answers
Answer:
Alnico is used for making permanent magnet because it can be easily magnetised in external magnetic field and It will not lose its magnetic property due to its high coercivity and low retentivity.
Alnico was the strongest permanent magnet available until rare earth magnets were developed. Learn more about these magnets, how they’re made, and what they’re used for here.
Before the development of rare earth magnets, alnico magnets ruled the magnet world.
While they are overshadowed and have largely been replaced by stronger rare earth magnets, alnico magnets are still commonly used in various industries for specific jobs such as high temperature handling equipment and manufacturing of sensors, to name a few.
What Is Alnico?
Excellent temperature stability, high residual induction, and relatively high energies.
Alnico is a combination of Al (aluminium), Ni (nickel), and Co (cobalt).
This development and introduction of Alnico meant that expensive electromagnets could be replaced with permanent magnets in essential devices like motors and generators.
Alnico magnets are permanent magnets that are primarily made of aluminium, nickel and cobalt.
How Is Alnico Made?
Alnico magnets are manufactured through either casting or sintering processes.
Cast magnets are manufactured by pouring a molten metal alloy into a mold and then further processing it through various heat cycles. The end product is a magnet with a dark gray exterior with a rough surface, but machined magnet surfaces have a shiny appearance.
Sintered magnets are manufactured by compacting fine alnico powder in a press, and then sintering the compacted powder into a solid magnet.
Where Are Alnico Magnets Used?
Despite being overshadowed and largely replaced by rare earth magnets, Alnico still perform better than their successors in specific situations and therefore are still used for many applications which require high operating temperatures.
Alnico magnets are most commonly used in the following:
Electric motors
Microphones
Engineering applications
Aerospace applications
Military applications
Sensors
Bearings
hope it helps...