Magnetic field of a neodymium magnet

What it is

A neodymium magnet is a magnetic element that is composed of neodymium rare earth boron and iron material. It has a crystal structure, tetragonal shape and formula Nd2Fe14B.

It was first created by General Motors in 1982. It is the strongest permanent magnetic element, the power of which is several times greater than usual. Equipped with a large magnetic induction of 12,400 gauss.

Note! This is a brittle alloy with the formula NdFeB, as well as a hard nickel-plated protective layer and the corresponding class. It is very popular and comes in various forms.

Advantages

The most common neodymium magnet is one that has an iron oxide alloy, which has good heat resistance, high magnetic permeability and low cost. Equipped with color coding, high coercivity, powerful magnetic field to hold objects suspended, compact size, light weight, affordable and wide range of applications. Has a long service life.

If an ordinary magnet works for 10 years and can be demagnetized, then a neodymium magnet does not lose its properties after 100 years. Another advantage is the shape. This product has a horseshoe shape. It gives the device a long service life. As for the cost, these are expensive products, but the cost is justified by excellent performance and impeccable reliability.

It is worth pointing out that the strength contained in neodymium magnets is another advantage. She is tall and it is impossible to find a competitor to her. This is a record type of indicator, the increase of which is impossible. Power is generated during manufacturing. Magnetization occurs after the alloy is formed. Thanks to existing technologies, the alloy is magnetized in such a way that the magnet has incredibly high power and this figure reaches a record.

Note! Power is a relative philistine concept. The force is stable, but it is measured using instruments. In this case, the readings depend on the thickness of the surface and cleanliness. The separation angle can have some influence.

Life time

The service life of the equipment, if used properly, is 30 years. Due to careless handling, the device may be damaged. The point is the lack of flexibility, as well as brittleness and cracking under heavy load. Falls, impacts, or reduced traction will reduce the life of the equipment. For this reason, it is necessary to avoid falls using parts that come into contact during movements.

Another extremely important point is the irreversible loss of magnetic properties due to heating. Therefore, grinding with cutting or drilling reduces the chain force and may ignite the alloy. If storage and operation are organized correctly, then magnetization is maintained for 10 years.

Screwdriver magnetizers

A screwdriver with a magnetic tip is, of course, good, but in some situations it can, on the contrary, interfere or even cause harm. For example, when working with electronics, a magnet can cause serious and irreparable damage to some parts.

And constantly juggling screwdrivers is quite stupid and inconvenient. Therefore, most craftsmen who often have to use a screwdriver use a special device, a magnetizer. With it you can quickly magnetize and demagnetize the tool without much manipulation.

Previously, such a service could be performed in workshops, but now, with the arrival of this device, there is no longer a question of how to magnetize a screwdriver at home.

Magnetizers are simple in design and use, which can change the corresponding parameter of metal objects. A huge advantage of the device is that it does not require additional connection to the network or recharging. And the small dimensions allow you to always have such a useful thing with you. And if we consider the design itself, the magnetizer consists of:

polymer case with slots for metal objects;

a set of magnets of different polarities.

Each of these holes is responsible for one or another function, magnetization, demagnetization. Usually, the slots are labeled, but even otherwise, you can very quickly check the parameters of each compartment.

The principle of operation is incredibly simple: place the object in the desired hole, wait a little. These devices differ in the size of the instrument itself and the size of the incision. The second parameter depends on how large the object needs to be magnetized.

They do not vary much in price, the usual price per piece varies from 100 to 400 rubles, although more expensive models can be found. Whether they are worth the money is up to everyone to decide.

Design

When answering the question of what a neodymium magnet is made of, we can point out that it is a rare earth element that contains an atom with lanthanide or actinide. The classic composition may still contain an additive. It is used to increase strength with endurance and resistance to high temperatures. Boron is used in small quantities, iron is a binding element. Thanks to this composition, greater adhesion is obtained. When connecting several ferrite rings, you can separate them with your hands. As for neodymium magnets, this cannot be done.

How to magnetize a screwdriver at home: tips, methods

In order for repairs, installation and other work to proceed quickly and efficiently, nothing should interfere, especially if it is a small screw that tends to fall off the screwdriver. For convenience, you can buy a special analogue with a magnetic tip.

But don’t throw your regular screwdrivers in the trash, because you can make these out of them too. To do this, most craftsmen use magnetizers, but there are also other ways to make such a miracle screwdriver. And for this you don’t need services, everything can be done easier and faster. Read on to learn how to magnetize a screwdriver at home.

How to use

Neodymium magnetic element is the strongest, exceeding analogues that are based on rare earth metal. In addition, neodymium is capable of maintaining a magnetized structure for a significantly long time. Such equipment can be used in various fields. For example, it is used in the manufacture of over-ear headphones with wind generators, motor wheels and scooters.

Note! Magnets are actively used in industrial, household, and medical fields. They are also used to carry out search work with a metal detector. They can often be found in plumbing fixtures or souvenirs.

Specific examples include the use of magnets in the development of medical devices, magnetic treatment of water, the creation of oil and technological filters, and the formation of actuators with highly sensitive sensors. In addition, they are needed to produce clothes with covers and shoes, and to create advertising, information and navigation materials.

Overall, neodymium is the most powerful permanent magnetic material that has high resistance to demagnetization, attractive power, and a metallic appearance. It has a long service life and consists of boron, iron and a metal of the lanthanide group.

The online store magnitstore.ru sells neodymium magnets, the adhesive force of which is ten times higher than their ferrite counterparts. There are universal products such as disks, rectangles, rods, rings. And targeted ones: search engines, mounts, car holders and others. All products, while relatively small in size, are very powerful. I would like to know what kind of field these strong neodymium magnets create and where does it even come from?

How to magnetize a screwdriver without a magnetizer

As in the case of a special screwdriver, a magnetizer can become unnecessary and an unjustified waste of money and time. This is especially true in cases where the need for a magnetized screwdriver is extremely rare.

And then there is a need to find a handy way to solve the problem. There are several methods on how to magnetize a screwdriver at home without using the device described above:

Using a powerful magnet. If there is such an item, then you can bring the instrument to the desired state in a few minutes. You need to move the screwdriver from the tip to the middle with a magnet. If you always need such a tool, then after work you can leave it on the magnet.

Using an improvised reel. In cases where there is no good magnet, and you need a screwdriver right now, you can make the missing item yourself. To do this, you need to wrap a metal object with paper and varnished copper wire.

For a good result, the wire will need a lot, two to four hundred turns around the selected object. The result is a coil to which voltage must be applied. To do this, you can use a battery, batteries, charger, and so on.

Through the voltage of the household, general power supply network. The same coil is also used here, only the voltage is supplied from the outlet. An important difference is the presence of a fuse that can protect against short circuits. You should be especially careful, because when connected, the fuse will burn out.

Each of these methods should be done following safety rules, otherwise it can cause harm to health. It is best if you do not have the appropriate skills or knowledge to seek help or advice from a person knowledgeable in this area.

Otherwise, each of these methods will be able to magnetize any metal object. The cheapness of each method should be considered individually, based on the availability of the necessary components.

Video on how to magnetize and demagnetize a tool without special equipment

Magnetic susceptibility

To understand why such a strong neodymium magnet and where its magnetic field comes from, you need to understand (without delving into complex formulas and graphs) at least the basic physical concepts of permanent magnetization.

Let's start with magnetic susceptibility. This is the name of a dimensionless quantity (denoted c), which characterizes the ability of a substance to be magnetized after it is in a force field. (By the way, the magnetic field of a neodymium magnet is such that it itself can magnetize products made from other alloys).

How to magnetize a screwdriver at home: tips, methods

Magnetization

Numerically, magnetic susceptibility is equal to the magnetization of a substance at unit field strength. Magnetization (denoted by J) characterizes the magnetic state of a particular physical body. If it is placed in a force field, then it will receive a certain magnetic moment M. In this case, its magnetization will be equal to the magnetic moment of a unit volume V. If the body is uniformly magnetized, then J = M/V. Magnetization is directly proportional to the strength of the force field that caused it. At one stage in the production of NdFeB products, they are placed in a very powerful force field, which gives greater magnetization. Therefore, the neodymium magnet has a simply enormous grip.

Magnetic moment is a vector characteristic of a substance that is a source of a magnetic field. (If, for example, an ingot of iron is brought into a force field and magnetized, then it itself will become a source of magnetism). It is created by the magnetic moments of elementary particles (atoms), which have an ordered orientation in space and therefore add up. The strength of a neodymium magnet is great, in part because it has a significant magnetic moment.

Why putting a magnet on a meter is a bad idea

To reduce water and electricity bills, some people put powerful magnets on their meters. Under the influence of a magnetic field, even during the consumption of water and light, the device does not rotate.

But a magnet is not an innocent way to save money. If a person uses water and electricity, but does not pay for them, he steals, that is, he commits an administrative offense. In the laws, this is called theft and is punishable by a fine, temporary arrest or community service.

Inspectors will probably know about the magnet

It seems that if you install a magnet only occasionally and pay a little on the bills, then no one will know about the violation. But inspectors have several ways to detect theft:

See the magnet. Usually they try not to let the inspectors in or quickly remove the magnet before opening the doors. But it may happen that the person who placed it will not be at home, the door will be opened by a child or a grandmother who has come to stay, or the residents will simply forget about the magnet. Then the inspector will take a photo of the violation and draw up a report, and then you will be issued a fine.
Check the indicator. Modern water and light meters have special indicators, or magnetic field sensors. It is enough to bring a powerful magnet to the meter once - and the indicator will change color forever. And some of the most modern devices can even send a message to the dispatcher, so they will instantly know about the magnet.
Measure the magnetic field. If a magnet has recently been placed on the meter, the magnetic field around it will be abnormally large. It can be measured using a special device - a Teslameter. And if the indicator can sometimes somehow be fooled, then the Teslameter cannot be fooled: it will clearly indicate that there was a magnet on the meter.

The Teslameter is expensive and is still rarely used, but gradually this method is becoming more and more popular. You can especially often find inspectors with teslameters in Moscow and St. Petersburg.

To record a violation and draw up a report, inspectors must come to the meter in person. To do this, management companies (MCs) arrange scheduled inspections every 1–2 years. Theoretically, you can adapt to them and use the magnet only immediately after the inspectors’ visit in order to save at least a little.

But if according to the general building meter the resource consumption is the same, but according to the sum of the apartment meters it is significantly less, this indicates theft on the part of the residents. In this case, the management company can arrange an unscheduled inspection and detect the magnet.

You will be punished for installing a magnet

Most often, on the basis of Government Resolution No. 354, they are required to pay the cost of resources tenfold. The cost is calculated according to average standards and multiplied by the time that has passed since the last inspection, but by a maximum of 3 months.

That is, if you install a magnet and it is discovered in six months, you will be forced to pay 10 times more than you would pay according to the standards for three months. Standards, by the way, are often too high.

Usually people spend less than the average per month, so the overpayment will be large.

This fine is not related to theft - it only relates to violation of the meter. If the Criminal Code decides to sue, the violator faces the following penalties:

A fine of 10–15 thousand rubles for the unauthorized use of electrical, thermal energy, oil or gas, according to the Administrative Code.
A fine of five times the value of the stolen property for petty theft up to 1 thousand rubles, according to the Administrative Code.
A fine for petty theft is from 1 to 2.5 thousand rubles in the amount of five times the value of the stolen property, or arrest for 10–15 days, or up to 120 hours of community service.

Theoretically, when more than 2.5 thousand rubles are stolen, the crime is no longer considered administrative, but criminal. He faces a fine of up to 300 thousand rubles or imprisonment for 1–2 years. But in fact, such punishments are not imposed in the Russian Federation for magnets on meters.

You can save money without a magnet

To save money, you don't need to install a magnet. There are several legal ways to pay much less for electricity and water:

Use LED lamps. They consume 8–10 times less electricity than conventional ones.
Turn off the water when you are not using it. This is useful to do even in small things, such as while brushing your teeth or in the shower while you lather up.
Always turn off the lights when leaving a room. You can install motion sensors so that the lights turn on and off automatically.
Install aerators on taps. They break the stream into small droplets, which creates greater pressure but reduces water consumption.
Use a washing machine and dishwasher. They use less water than hand washing or washing, and they also use cheaper cold water rather than hot water. Electricity consumption increases, but the final payment decreases.
Fix all leaks in a timely manner.
If the tank has one flush mode, place a bottle filled with water in it. This will slightly reduce the volume of the tank. There will still be enough water to rinse, but the consumption will decrease.
Install a tank with two flush modes to waste less water.
If cold water flows for a long time before hot water, you can drain it into a bucket. Then the water can be used for flushing, watering plants or other purposes.

Reasonable consumption of resources will help you save money even without magnets, so you don’t have to fear inspections and fines.

Source: https://Lifehacker.ru/magnit-na-schyotchik/

Magnetic induction

The value of the residual magnetic induction (designated Br) allows you to understand how dense the power flux or how strong the magnetic field is produced by a given magnet in a closed system. Magnetic induction (designation B) is the reading of a gaussmeter obtained by measuring the power of the force field on the surface of a particular magnet. Both quantities are expressed in Tesla or Gauss (1 Tesla = 10,000 Gauss). Since the magnetization of a neodymium magnet is significant, its magnetic induction is also high, from 1.0 to 1.4 Tesla. For comparison, ferrites have from 0.1 to 0.4 T.

The volumetric magnetic susceptibility of any substance is numerically equal to the magnetization of its unit volume divided by the strength of the magnetizing force field: c = J/H. Paramagnetic materials have positive magnetic susceptibility because the direction of the molecular current field coincides with the direction of the external force field. (For diamagnetic materials it is the other way around).

Demagnetize magnets

Man has been using magnets in various areas of his life for a long time. Often we do not notice their presence in the devices around us and the additional convenience of their use. Today, the vast majority of household appliances and appliances are created using magnets.

However, many unexpected problems arise in everyday life, especially of a technical nature. It happens that you need to maintain or strengthen the effect of a particular magnet, and especially vice versa - demagnetize it. Let's dwell on the last problem - how to demagnetize permanent magnets?

After reading a selection of our practical tips, you will find out how, in what way, and whether it is possible to demagnetize “home” magnets without outside help.

Magnetization of paramagnetic materials

A neodymium magnet, whose adhesive force is so strong, is paramagnetic. It has positive magnetic susceptibility. In its normal state it does not have any noticeable magnetic properties. The reason is this. In it, like in other paramagnetic materials, the magnetic moments are compensated because there is no ordered arrangement of elementary particles. That is, in the case when there is no external magnetizing field, each neodymium atom still has some kind of “microscopic” magnetic moment. But neodymium does not have the same structure that is inherent in ferromagnets. Therefore, the atoms are randomly oriented, the magnetic moments are directed in different directions. The vector addition of their numerical values results in zero, which means that the magnetization of the entire ingot is also zero. How is it that neodymium magnets have such a strong attractive force?

Everything is very simple. When a paramagnetic material enters an external magnetic field, its atoms turn (orient) in one direction. After which the vector addition of unit moments will no longer be equal to zero. As a result, neodymium receives a total magnetic moment J. It is directly proportional to the external field strength H and directed along this field. When making a neodymium magnet, a magnetic field for its magnetization is created with an induction of about 3 - 4 Tesla.

There is one important point that is useful to know for those who are interested in the properties of NdFeB. The magnetic ordering of atoms is counteracted by the thermal energy of the substance. Despite the fact that neodymium magnets develop a very large force, the paramagnetic susceptibility of the main element Nd largely depends on temperature. This is why the NdFeB alloy cannot be heated to + 80 degrees C and higher - the atoms will lose orientation and the vector sum of their magnetic moments will again become zero.

This is the explanation of why neodymium magnets have an attractive force at all, and even such a large one. The two main points are that Nd is paramagnetic and a large force field is created to magnetize it. This is, of course, a simplified view. To understand why a neodymium magnet is reinforced with iron and boron, you need to master quantum physics.

We wrote this article to answer the question about classes of magnets, their standards, and physical characteristics.

Despite the fact that the magnets we offer are called neodymium, they can be very different from each other, because each magnet has its own physical characteristics, not just size, shape and coating. Therefore, the question of which neodymium magnets are of interest to you should not confuse you. In this article you will get answers to many of your questions.

Screwdriver magnetizers

Previously, such a service could be performed in workshops, but now, with the arrival of this device, there is no longer a question of how to magnetize a screwdriver at home.

polymer case with slots for metal objects;

a set of magnets of different polarities.

They do not vary much in price, the usual price per piece varies from 100 to 400 rubles, although more expensive models can be found. Whether they are worth the money is up to everyone to decide.

What do the letters and numbers mean in the classes of neodymium magnets?

Often, we, as manufacturers and sellers, want to hear the technical characteristics of the magnet, namely the letters and numbers in which they (the technical characteristics) are encrypted. And the buyer often thoroughly knows his field of application of magnets, but does not know the nomenclature, especially the international one. So, let's begin to understand the international nomenclature of magnets, namely classes, technical characteristics and designations.

First of all, neodymium magnets are divided into classes, which are designated by letters and numbers (for example, N35), which contain basic information about the magnet. Below is a standard nomenclature table of characteristics of neodymium magnets (look in the left column - the classes are indicated there).

In the table, we presented all numerical values in two units of measurement. The first, without brackets, is the measurement value in the SI system (this is the system in which our country operates), and the second (indicated in brackets) is the measurement in the international CGSE system (European standards). For your convenience, we decided to indicate both units of measurement in the table.

Neodymium magnet characteristics table

We begin to study the table from right to left. As you can see from the right column of the table, the main class difference between magnets is their operating temperature of use, that is, the permissible maximum temperature, above which the magnet begins to lose its magnetic properties. Thus, the temperature range of use of the magnet is indicated by the letter part of its marking (left column). Let's decipher these letters:

Magnets brand N (Normal) – can be used at normal temperatures, that is, up to 80 degrees Celsius;
Magnets brand M (Medium) – can be used at elevated temperatures, that is, up to 100 degrees Celsius;
Magnets of grade H (High) – can be used at high temperatures, up to 120 degrees Celsius;
SH (Super High) magnets
Magnets of the UH (Ultra High) brand – can be used at temperatures up to 180 degrees Celsius;
Magnets brand EH (Extra High) - can be used at temperatures up to 200 degrees Celsius.

It is worth mentioning that negative temperatures do not affect the magnetic properties of most magnets.

The numbers indicated in the magnet class designation: N30, 33M, 35H, 38SH, 40UH, etc., indicate Magnetic Energy (fourth column of the table), measured in kiloJoules per cubic meter. This criterion of magnets is responsible for their power or the so-called “tearing force,” that is, the force that must be applied to the magnet in order to “tear” it from the surface. It is necessary to understand that the surface (steel sheet) must be perfectly flat, and the applied force must be perpendicular to the sheet. These are the so-called ideal or theoretical conditions. It is absolutely clear that the higher the digital designation of the magnet, the higher its pull-out force.

The magnets are connected to each other - how to separate them

How to demagnetize a magnet from a magnet (disconnect), especially if they are powerful? Let us immediately make a reservation that it is useless to separate powerful magnets by simply breaking them, and you can get injured. In this case, you can also give at least two pieces of advice:

Method 1: Using diamagnetic metal sheet

Using a metal wedge made of some diamagnetic material (duralumin, copper, etc.), try to widen the gap between the magnets, but be careful - do not use an iron hammer (it attracts).
Insert a sheet (can be metal) into the gap that is larger in area than the magnets, which will serve as a guarantee that everything can come back and the magnets will attract each other again.
Secure the lower magnet, and begin to move the upper one until you feel that it is freed from the attraction of the lower one.

Method 2. Using plywood

To separate the magnets, a sheet of thick plywood (10 mm) is used. A hole is made in it for the magnet (if it is impossible to create a gap between the magnets). This sheet will serve as a kind of stop for one of the magnets during the separation process.
Disconnection occurs in the same way as in the first example.

Everything described above are little tricks mainly for amateur locksmiths. And now a little about the twists and turns with magnets during shopping, which most of our lovely ladies so adore.