How To Demagnetize Something

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Magnets are simple yet fascinating things to play around with and it’s interesting to find out if you can actually demagnetize something that is magnetic even without any special tool or equipment. Of course, we’re talking about small-scale magnets and not the ones that are used to operate heavy machinery.

In any case, magnets are fascinating and in order to learn how to demagnetize something, you should try to understand more how magnets work.

What Are Magnets?

Magnets attract other magnets or other magnetic materials at a certain distance. They do this invisibly through a force called magnetic field. To make it simpler, magnets are objects that produce magnetic fields. They attract metals like iron, nickel, and cobalt. The lines of force of the magnetic field exit the magnet from its north pole and enter through its south pole.

Here are some more fun facts about magnets:

  • A magnet has two ends called poles. One of them is a north pole and the other is a south pole. The north pole end of the magnet attracts the south pole of another magnet and vice versa. In other words, similar poles repel and opposites attract.
  • The north pole of a magnet points toward the Earth’s north pole and the same goes for the south pole. This is because the Earth has magnetic materials and it acts like a giant magnet.
  • Cutting a bar magnet in half will result in two new smaller magnets both with their own north and south poles.
  • Running a magnet over an unmagnetized piece of magnetic material for a few times will convert the material into a magnet as well. An example of this is an iron nail. This is magnetization. It’s a great thing to learn if you want to know more about how to demagnetize something.

If you want to know more about magnetism, this is a great informative piece on magnetic fields and magnetic force. For more information about metals, check out this guide if a miter saw can be used to cut metal.

To help you visualize it, even more, you can watch this documentary on the science behind magnets and how do they work.
[youtube https://www.youtube.com/watch?v=MZtTVsIOA9c?rel=0]

What Are Electromagnets?

Electromagnets produce magnetic fields but only when electricity travels via their wire coils. To magnetize electromagnets, an electrical current should pass through the solenoid to create a magnetic field. Of course, this is a whole other topic if you want to demagnetize something that is an electromagnet.

Types of Magnets

So, let’s break it down. How many types of magnets are there in the world?

  • Ceramic

    Ceramic or Ferrite magnets are like the ones in your refrigerator magnets or the ones in elementary school science experiments. They contain iron oxide in a ceramic composite and are not particularly strong. They’re inexpensive and are one of the most common types of magnet.

  • Neodymium Magnets

    These have a rare earth magnetic material and have a high coercive force with extremely high energy. Because of its high energy level, it can be very small and compact in size. These are very strong magnets and are difficult to demagnetize.

  • Samarium Cobalt

    These are also very strong. It’s not easy to demagnetize something with this type of magnet. They can withstand temperatures of up to 300 degrees Celsius. They can be very expensive and have low mechanical strength.

  • Alnico

    Alnico magnets are stronger than ceramic magnets but not as strong as neodymium. Despite that, it’s easy to demagnetize something that is alnico magnet.

There are other subtypes of magnets, but those are the main ones you should get to know in order to learn how to demagnetize something.

How to Demagnetize

Is it really possible to demagnetize things? If yes, how do you do it?

Let us look at some of the techniques.

  • Heating

    You should heat a magnet past its Curie point to destroy its long-range ordering. This will provide energy to the magnetic dipoles which will cause them to free themselves from the initial order, destroying and reducing the ordering of the magnetic dipoles in the process. You must heat a magnet for a long duration in order for it to be effective in demagnetizing things.

  • Hammering

    Hammering should be on both poles of the magnet. Hammer it many times so that the vibration causes the magnetic dipoles to randomize. It will destroy the long-range ordering within the magnet.

  • Electric Current

    An AC current produces a magnetic field of changing direction near the magnet. When an AC current passes through a solenoid, it creates the magnetic field around the object which destroys the alignment of domains. This is an effective way to demagnetize something. In an electric current, ceasing the flow of current eliminates the magnetic field but a slight field may remain in the core material due to hysteresis.

    Alternatively, you can also rub the magnetic object vigorously in both directions with a metallic object. This will cause it to lose its magnetic properties.

  • Demagnetizer

    Another way is to use a magnetizer demagnetizer which is a tool that will magnetize and demagnetize the tips of screwdrivers and other kinds of steel tools. It will only take seconds to magnetize or demagnetize something. You can just insert the tooltip in the demagnetizer hole and shake the tool from side to side for a few seconds.

 

Take a look at some of the readily available magnetizer demagnetizers:

Farmunion Electrical Demagnetizer Tools

HHIP 3401-0006 Economy Demagnetizer

EuroTool Demagnetizer/Magnetizer

Just a few extra notes when trying to demagnetize something:

The main concept when you demagnetize something is to cause disorder to the unit magnets within the magnetic material.

Magnetism is the result of the alignment of magnetic dipoles in an object in a general direction. These magnetic dipoles or unit magnets need to be aligned in one direction. To demagnetize something, you need to cause disorder to the unit magnets to randomize them.