What are the Different Magnet Types?

Magnets generate a kind of force field that repels or pulls specific materials like iron or nickel. But what are they actually made of, and what are the different types out there? Here are some things that you need to know.

It’s worth noting that not all magnets are made up of the same elements, and therefore, they can be explicitly categorized according to their source of magnetism and composition. Temporary ones act like the permanent variety but only when they are in the presence of a magnetic field but lose it.

These electromagnets are wound wire coils that act like magnets when electrical current passes through. When you adjust the current’s direction and strength, there will also be changes in the magnet itself. Below is the breakdown of the various types available.

Neodymium Iron Boron

The neodymium iron boron is a rare type with a very high coercive force. The range of energy products is exceptionally high, and this is almost 50 MGOe. This is a permanent type that can retain its force field, as you can find in neodymium magnets, and it’s durable in nature. Since this has a higher energy level, it’s usually compacted in nature and is manufactured in smaller sizes.

However, the neodymium iron boron with the element NdFeB is usually known for its lower mechanical strength. They are brittle with low corrosion resistance, especially if they are uncoated. If you treat them with nickel plating, iron, or gold, they can be applied in many things and are very challenging to demagnetize.

Samarium Cobalt

Like the NdFeB, the SmCo magnet is complicated and very strong to demagnetize. They are very resistant to temperature changes and oxidation, and they can withstand a temperature of up to 300-degree Celsius. Currently, the samarium cobalt is identified based on the energy range of the products. The first one has an energy range of 15 to 22 MGOe, and it’s called the SM1Co5 Series, and the other one has a range of 22 to 30 MGOe which is called the SM2Co17. However, they have lower mechanical strength and are generally expensive in nature.

Alnico

The alnico has gotten its name from the first two letters of the metals it’s made of, aluminum, nickel, and cobalt. These magnets have great features like temperature resistance, but one can easily demagnetize them. They are sometimes replaced by rare earth magnets and ceramic in industrial applications. They are manufactured mainly by casting or sintering, which may yield different characteristics.

Sintering processes may produce or enhance the mechanical traits of the alnico. On the other hand, casting will result in a higher energy product and usually enables the magnets to get more complex features. Learn more about alnico on this site here.

Ferrite or Ceramic

The ceramic or ferrite is often composed of sintered strontium carbonate, barium, and iron oxide. They are affordable and can be quickly produced through pressing or sintering.

However, since these are brittle, they may require a diamond wheel grinding. These are just some of the most common types used, and they are not easy to demagnetize. They are very durable as well.

Temporary Types

Electromagnets

The electromagnets are often produced by winding wires into various loops where the core material is called a solenoid. To activate the force field, electricity or current is usually passed into the core of the solenoid, and the interior is usually the strongest part. The strength is according to the number of loops and the current power.

The core material at the center or solenoid will also affect the overall strength of the electromagnet. However, if you wrap this around a non-magnetic material like wood, the field will not be strong. The overall strength can increase dramatically if the core is composed of iron and other ferromagnetic material. So why is this considered a temporary type? This is because if the battery’s power dies, so will the current, and the field will disappear.

Applications to Know

These are used as sweepers on airfields or plant floors. They are usually used to separate the impure materials during the process of recycling or manufacturing. They are commonly found in videotapes, radios, telephones, televisions, and speakers in electronics. Usually, they are used in computers, telephones, and televisions because they are very strong for the same reason that they are used in cranes and in on-off mechanisms that require heavy-duty lifting.

Cool Facts about the Magnets

1. They Come in Various Flavors

Ferromagnets – These are substances made up of nickel and iron where the spins are essentially aligned with unpaired electrons. They make excellent permanent magnets in general. You might be looking to levitate some objects, and if this is the case, the diamagnetic materials are one of your best options. They essentially generate fields opposite to their location, and this principle is pretty common in Maglev trains.

2. Magnetism is Essentially a Form of Light

You might be wondering why magnets stick in the first place. The answer is that they’re essentially exchanging photons, and the particles are made up of light. However, unlike the photons you can see out of a desk lamp that essentially reflects the light around you, the photons in magnets are virtual and invisible to the eyes. Read more about these magnetic lights in this url: https://www.sciencedaily.com/releases/2020/09/200914112140.htm.

These photons are force carriers and may occur in static electricity. However, they can exchange momentum, and there’s a chance that you can repel them or stick them to things. This is known as electromagnetism which is usually light with an electromagnetic wave.

3. They Came from Lodestones

Ancient people from China and Greece have recognized that lodestones have features not seen in other types. They were close to the truth as lodestones are forms of iron oxide or magnetite formed with the slow cooling of magma. They attract iron metals and are aligned with the earth’s magnetic field. The lodestones were even considered to be the first compasses of ancient civilizations.