What are magnet balls? Easy guide to understand this supertrend!

Magnet balls VS regular magnets

The main difference between magnet balls and regular magnets is their relative strengths. Magnet balls are more than ten times stronger than the strongest ceramic magnets. So, why are magnet balls so much stronger?

Let us start by looking at the material differences between magnet balls and regular magnets. Magnet balls are made of Rare Earth magnets which are made from combinations of Rare Earth elements.

Magnet Balls
“Regular Magnets”

Made of Neodymium
Made of ferrite materials (ie Iron)

Remanence value from 1.0 to 1.4 Tesla
Remanence value from 0.2 to 0.4.

Higher Coercivity
Lower Coercivity

Must be used at low temperatures
Can withstand high temperatures

There are seventeen Rare Earth elements:

Cerium (Ce)
Dysprosium (Dy)
Erbium (Er)
Europium (Eu)
Gadolinium (Gd)
Holmium (Ho)
Lanthanum (La)
Lutetium (Lu)
Neodymium (Nd)
Praseodymium (Pr)
Promethium (Pm)
Samarium (Sm)
Scandium (Sc)
Terbium (Tb)
Thulium (Tm)
Ytterbium (Yb)
Yttrium (Y).

Although these elements are classified as Rare Earth elements, a majority of them are not in fact rare. Of the Rare Earth elements Neodymium and Samarium are the two used to construct Rare Earth magnets. Magnet balls are neodymium magnets.

The strength of magnets can be evaluated using three main measures: remanence, coercivity, and Curie temperature.

Remanence measures the strength of the magnetic field produced by the magnet, coercivity measures the magnet’s resistance to being demagnetized, and the Curie temperature determines the temperature at which the magnet loses magnetization.

We will address the three measures mentioned above in our explanation for why magnet balls are stronger than regular magnets.

The greater strength of Rare Earth magnets is due to two main factors:

High magnetic anisotropy
High magnetic moments

First, the crystalline structures of Rare Earth magnets have very high magnetic anisotropy. Magnetic anisotropy has to do with the direction in which a magnet is magnetized.

A magnet with high magnetic anisotropy magnetizes along a specific axis and is very difficult to magnetize in other directions.

Moreover, this resistance, of the crystal lattice of Rare Earth magnets, to changing their direction of magnetization means that they also have a high resistance to being demagnetized. Thus, Rare Earth magnets have higher coercivity than regular magnets.

The second reason for the magnet balls’ greater strength is because their atoms can have high magnetic moments. A magnetic moment describes the strength and orientation of a magnet.

The atoms of Rare Earth magnets can have high magnetic moments because they contain more unpaired electrons. In other elements, almost all electrons exist in pairs which causes them to cancel out each other’s spin.

However, when the electrons remain unpaired they align to spin in the same direction and produce a magnetic field.

Thus, Rare Earth magnets produce a stronger magnetic field meaning that they have a greater remanence.

For a better idea of exactly how much stronger Rare Earth magnets are than regular magnets, we can compare their remanence values.

For example, a neodymium magnet has a remanence value from 1.0 to 1.4 Tesla while a regular ferrite magnet composed of mainly iron only has a remanence value from 0.2 to 0.4.

Now we know that magnetic balls have higher coercivity and remanence than regular magnets. However, Rare Earth magnets will lose their magnetization if heated above their Curie temperature.

On their own, Rare Earth magnets have a Curie temperature below room temperature so they can only be used at low temperatures.

However, when combined with other elements like iron or nickel they are able to work at higher temperatures. We will look at the makeup of magnet balls more closely in the next section.

What are magnet balls made of?

Magnet balls are made of neodymium, a type of Rare Earth magnet.

Neodymium was invented in the 1980s and is currently the strongest permanent magnet in the world. They are also referred to as NIB magnets because they consist of an alloy of Neodymium, Iron, and Boron.

Neodymium magnets can have different grades depending on their strength, with higher grades being more powerful magnets.

Currently, the highest grade of neodymium available is N52. The N stands for neodymium and the number following then indicates the grade.

The number for a magnet’s grade actually comes from a physical property: the maximum energy product of the magnetic material. But how do you measure the strength of a magnet?

There are two main ways to measure the strength of a magnet. The first is pull force which looks at how much force you must exert in order to pull the magnet away from a surface.

The second common measure of a magnet’s strength is its magnetic field strength. The measurement of magnetic field strength looks at the field’s strength and direction at some point near the magnet. The strength of the field is affected by factors like the size and shape of the magnet and even the place where the measurement is performed

There are two main production methods for making magnet balls. The first is the sintered magnet process which begins by melting the raw materials in a furnace and pouring it into molds.

The product is then removed from the molds and pulverized to make a powder which is sintered into blocks.

Sintering is the process by which the powder is pressed into the blocks. The blocks are then processed and magnetized to create the final magnets.

The second is a more complex bonded magnet process discovered in 2015 by a Japanese company.

This method involves melting a neodymium alloy into thin ribbons which are then powdered and mixed with a polymer. This mixture is then compressed to form bonded magnets.

Bonded magnets have a weaker magnetic field than sintered magnets but they can be shaped and molded more effectively. This makes them particularly useful for tools that require intricately shaped magnets.

Since the neodymium magnets contain iron, they will rust if left exposed to the air. Furthermore, neodymium reacts with oxygen and oxidizes if left untreated. Thus, the magnet balls are coated to protect them from corrosion.

The most common materials used to coat neodymium magnets:

Nickel
Gold
Chrome
Copper
Epoxy resin
Zinc

The most common coating material is nickel and magnet balls are often triple coated with the three layers being nickel, copper, and nickel.

The gold coating is used more for decorative purposes because it is very thin and rubs off easily. In general, a very thin layer of gold is used to cover a magnet which is already triple coated Ni-Cu-Ni.

A chrome coating stands up better to rubbing and lasts longer. Like the gold coating it is layered over the nickel, copper, and nickel triple coating.

Copper is a less popular option because it is more vulnerable to rubbing and is less resistant to corrosion. Additionally, copper is subject to color change from oxidation.

Another coating material is epoxy. The problem with using an epoxy coating is that it is not shock resistant and thus it is vulnerable to crumbling.

Even when it is layered over a Ni-Cu-Ni triple coating the smallest crack can cause the magnet to break down faster.

Finally, the magnet balls may have a zinc coating. Unlike many of the other coating options, zinc is used on its own without Nickel or Copper underneath. Because of this, it is more susceptible to corrosion than a magnet with a Ni-Cu-Ni coating.

There are some special coatings which are not used as often. One of these coatings is silver. Like gold, a thin layer of silver is placed over the nickel, copper, and nickel triple coating and is there for solely aesthetic purposes. Also like the gold coating, it is a very thin layer which will rub off after prolonged use.

Another less common coating is Teflon. Like with zinc, the magnets would be coated with just Teflon and not the triple coating. The Teflon would be applied in a thick layer and would be nearly waterproof and mostly unaffected to rubbing.

As a side note, this is one area in which ferrite magnets have an advantage of neodymium magnets because they are weather-resistant on their own without any coating.

How and where are magnet balls used?

Magnet balls are intended to be used as recreational and stress reliving toys for adults. They have been manufactured and sold under many names including “Buckyballs” and “Zen Magnets”.

Magnet balls fall into a similar toy grouping as products like fidget spinners and stress balls. They are moldable magnets that keep your hands occupied thereby relieving stress.

However, the material from which magnet balls are made, neodymium, has a number of important applications apart from being a fun and, at times, controversial toy. Rare Earth magnets are so useful because they are simultaneously very powerful and compact.

When Rare Earth magnets were first discovered they were not widely used because they were very expensive to produce. However, as they became cheaper they quickly found wide usage.

Some uses of neodymium magnets are:

Hard disk drives
Wind turbine generators
Audio equipment: speakers, headphones, etc.
Dentures
Magnetically coupled pumps
Door catches
Motors and generators
Jewelry
MRI scanners
Lifting machinery
Magnetic therapy
Crafts and model-making
Print finishing
Hanging artwork

Hard disk drives record and store data by magnetizing and demagnetizing a thin film. Neodymium magnets are used to direct the read/write mechanism in the drive.

You probably encounter them most directly in earphones or headphones where they have been very useful because a neodymium magnet can produce the requisite magnetic force that would otherwise require a much larger ferrite magnet.

Neodymium magnets are also used in medical equipment like magnetic resonance imaging (MRI) machines. They have replaced the bulky superconducting coils which has greatly reduced the weight of these machines from 100 tons to less than 20 tons.

Another medical application of these magnets is for magnet therapy. Though this therapy is still in the trial phase, preliminary studies have shown that magnets can has some effect on individuals with specific ailments.

For example, in a 12-week randomized trial, patients with multiple sclerosis received low frequency magnetic impulses. The study found that the magnetic stimulations helped reduce fatigue in the patients.

Another application of this therapy involved a large amount of magnetized water which supposedly supplied magnetic energy and rods which were used to direct it to afflicted areas in the patients. It was not clear if this therapy had any effect on the patients’ health.

Magnetic therapy is not a new idea. In fact, it has been used for centuries to aid in pain relief. The strongest anecdotal evidence in support of magnetic therapy is in relation to its use in treating musculoskeletal disorders.

A final example of magnetic therapy is scalp acupuncture. The treatment involves placing small magnets along the scalp and charging them intermittently over an extended period of time. It can also be combine with needles to help relieve high blood pressure and headaches.

These magnets have some even more unusual applications like in dentures, where tiny neodymium magnets are strong enough to hold together the attachments and fit easily into the mouth. Another unusual application of these strong magnets are in door catches in commercial buildings.

The magnets are also used in print finishing where, because of their small size, they can be used to make discreet closures for binders and packaging.

You might remember how teenagers tried using magnet balls to imitate fake piercings. Interestingly, neodymium magnets are actually used in jewelry particularly in the clasps with magnet balls just 5mm in diameter, the size of “Buckyballs”, being strong enough to be effective.