Magnetization is the process by which magnets become magnetized and acquire the characteristic properties of magnetic elements. Due to this phenomenon, the object acquires the strength to attract or repel a metallic object. There are different types of magnetization of a magnet, depending on the line of induction, in other words, the way the magnetic field is represented.
Ferromagnetic materials can be magnetized by magnetic induction whereby magnetic fields produce electric fields. The induced magnetism is created by the strength of such a field.
The 3 types of magnetization that we can find depending on the different magnetizations are:
Axial: the axial magnetization type is characterized by having a magnetization that is from one side of the magnet to the other, in other words, the magnetic induction lines go from one pole to the other (from top to bottom).
Below, we can find several magnetizations with different numbers of poles that both have an axial magnetization.
| Representation | Number of poles |
 | Single pole |
 | Two poles |
 | Four poles |
 | Multiple poles |
 | Unipolar |
 | Four poles on one side |
 | Unipolar, single pole |
As we can see all poles have a horizontal magnetization.
Radial: radial magnetization is characterized as the magnetization of rings, discs, and cylinders. In addition, the representation of the magnetic field lines is found across the radius. This type of magnetization is found in the manufacture of motors, sensors, and actuators. Its orientation is multi-directional, i.e. it is found across the radius.
| Representation | Number of poles |
 | Single pole |
Diametral: material that has been diametrically magnetized has a magnetization that lies across the width of the magnet, i.e. across the diameter (from right to left). As we can see all poles have a vertical magnetization.
| Representation | Number of poles |
 | Single pole |
 | Multiple poles |
 | Diameter and direction, one pole |
 | Diameter and direction, four poles |
To know the magnetization process of a magnet, we must bring it close to some other metallic element.
The difference between axial and diametral magnetization lies in the magnetization force about the location of the magnetic field. Axial magnetization, having the direction of magnetization horizontally, the force will predominate on those faces. On the other hand, diametral magnetization is magnetized in its diameter. In addition to these two types, we find the radial magnetization which has multiple poles so it has a wider range of applications.
Magnets are objects that we use in our daily life, depending on the application to which we want to destine it, we will use one type or another. The strongest magnet and therefore the most dangerous magnet is the neodymium magnet. If this type of permanent magnet has large dimensions, there may be a risk of serious accidents due to its large magnetic field.
As we already know in everyday life magnets attract aluminum and gold, among other materials, we must be careful when using them and in the case of large magnets, store them properly to ensure the welfare of the people around them, as well as objects and furniture that are nearby.
When dealing with magnets with a high magnetism we have to take into account several factors such as:
Magnets of large dimensions have a great force of attraction, so the lack of attention can cause the breakage of some areas of the magnet causing shocks and even a magnet of large dimensions can originate hemorrhages... On the other hand, if the ocular fragments come into contact with the eyes, these can cause eye injuries.
The alteration of air transport: the presence of magnets or any other magnetic element in any air transport, mainly in airplanes, can produce an alteration of the navigation control devices causing fatal accidents.
In addition to the dangers of magnets and working with large magnets, there are also possible accidents caused by smaller magnets.
The most recurrent accidents with this type of magnet are:
Keep it out of the reach of children:since most magnets are made of nickel or rare earth and these could be allergic to children. On the other hand, when dealing with magnets of short size, they could be ingested into the body causing fatal complications.
Conductors of electric current, many people are unaware of this property that magnets have, which can produce a variation in the functioning of pacemakers and defibrillators. In the same way, we have to take into account the exposure of pregnant women, since these cause biological effects of static fields causing hospital diseases originating nosocomial infections (NI), in other words, infections that are generated at the time of admission of the patient.
IMA receives the visit of the municipal technician Laura Olivera Martin, on the occasion of our participation in the Work, Talent and Technology Project as suppliers of goods related to the health chain.
The purpose of this project is to increase and promote quality employment and competitiveness based on people's talent. It also aims to improve sustainable economic development and collaborate in reducing social inequalities.
IMA, the leader in the magnetic sector, participates in different technological projects related to the medical sector.
Our systems and solutions are applied in:
The development and design and manufacturing of imaging systems.
Overmolded magnets used in X-Ray equipment.
Magnets for laparoscopic surgery technique.
Injected magnets used in cardiac rhythm disturbance controllers.
Magnets are used in the manufacture of high voltage defibrillators.
Multipolar magnets comply with FDA regulations for the protection of biological materials such as vaccines or serums.
Voltage stabilizers guarantee the proper functioning of vital elements in hospitals.
Isolation transformers for patient safety in operating rooms.
Electromagnets with an infinite number of uses.
Magnetic systems and uninterruptible power supply machinery are used in operations or medical tests.
Magnets used in orthopedic systems.
All of them ensuring a correct and quality operation according to the requirements of our customers.
Our actions and initiatives reflect our commitment and awareness of the fight against climate change and a truly sustainable energy transition.
Therefore, at IMA we have implemented different initiatives focused on energy sustainability, renewable energies, and sustainable mobility: installation of solar self-consumption, installation of bicycle parking inside the warehouse, adhesion to the Voluntary Agreements Program, a mobility diagnosis, the acquisition of a 100% electric vehicle for the commercial area and the installation of two chargers for electric vehicles.
These last two actions,the purchase of the vehicle and the installation of electric chargers, have been awarded 1st and 2nd prizes in the category of Energy Sustainability and Renewable Energies in the 2020 Innovative Projects Awards granted by the Ripollet City Council. All our efforts add up.
Hook magnets are already implemented in several sectors such as gastronomy, automotive, advertising... Hook magnets are widely used as they only require a metallic surface, they can be made of neodymium magnets or ferrite magnets .
Hook magnets can be of different types of magnets, but the most common for their high holding strength is usually neodymium magnets, these are used in order to install ornamental objects, office wiring...
Neodymium hook magnets are an excellent choice to stick and hold any object on surfaces made of ferromagnetic materials (nickel, iron, or cobalt). This is a good alternative, since this way we avoid drilling or screwing the wall and prevent leaving a mark: this is a faster, easier and cleaner solution.
We can use them in different areas:
Automotive sector: In this sector we can see them inside the vehicle, to hang our belongings in the trunk. Other utilities of the hook magnets can be found in the mechanics to keep in an orderly manner all the tools.
Gastronomy sector: Restaurants can use the hook magnets to maintain a tidy space, as this facilitates agility both inside and outside the kitchen.
Industrial sector: Hook magnets can be used for canopies, temporary signage, suspended ceiling cables.
Advertising sector: This type of magnet can be used to hold advertising slogans or to display and present your products. They are a very visually attractive option to capture the attention of consumers.
Neodymium hook magnets are an excellent choice to stick and hold any object on surfaces made of ferromagnetic materials (nickel, iron, or cobalt). This is a good alternative, since this way we avoid drilling or screwing the wall and prevent leaving a mark: this is a faster, easier and cleaner solution.
You can find a wide variety of hook magnets, in different colors and shapes, at your fingertips. You will find hook magnets made of different magnetic materials such as neodymium hook magnets or ferrite hook magnets. White hook magnets are particularly popular because they fit virtually anywhere. Transparent hook magnets are ideal for incorporating into any location, whether it is an outdoor location such as a stall or an indoor location such as an office. Contact us and we will provide you with the best solution for your needs.
The temperature coefficient symbolized as α is a property, which does not depend on the amount of substance or size, of materials that quantify the relationship between the alteration of this property of a material and the temperature range. This temperature coefficient is expressed in K (according to the International System of Units).
The constant α is obtained with the following formula:
R0 = initial resistance
ΔT = temperature change
ΔR = change in resistance
The negative temperature coefficientof resistance is called NTC (Negative temperature coefficient), it is given to the reduction in resistance with an increase in temperature, this coefficient is usually found in non-metallic substances and semiconductors.
While the positive temperature coefficient of resistance is called PTC (Positive temperature coefficient), it occurs when the temperature increase increases the resistance value of a material. PTCs can be found in pure metals.
Below, we can see the table of coefficients of variation of resistance per degree Celsius of temperature.
Material α °C Material α °C
Carbon
0.0005
Niccolite
0.0002 Nickel
0.0047
Copper
0.00382 Advance
0.00002
Kruppine
0.0007 Wolfram
0.0045
Tungsten
0.0041 Gold
0.0034
Lead
0.0037 Nichrome
0.00013
Platinum
0.0025 Aluminum
0.0039
Iron
0.0052 Manganite
-
Brass
0.002 Silver
0.0038
Mercury
0.00089 Tin
0.0042
Phosphor bronze
0.002
If the temperature changes and increases by 10°C, the rate of change of chemical or biological systems will vary; this can be found with the temperature coefficient Q10, which is needed in chemical reactions.
Thetemperature coefficient of resistance is the measure of alteration that we find inthe electrical resistanceof some substances of the degree of temperature variation.
The resistance (R) for a temperature variation (∆t) in degrees Celsius is found due to:
R = R0 -(1+α - ∆T)R0 =reference resistance
α =temperature coefficient
The PT-100 sensor, which is a temperature sensor, is required to know the resistance performance at changing temperatures of the medium.
The temperature coefficient of the electrical resistance establishes the increase or decrease of the electrical resistance according to the change of temperature and the essence of the different materials. This coefficient is found thanks to the resistance formula that varies depending on the temperature variation.
On our website, we have different types of magnetic control equipment meet the needs of our customers.
The air gap is the air space between thestatorcore and the rotor of the electrical machine within a magnetic circuit. In electrical machines, the reluctance of the air gap can sometimes be overlooked without committing a major flaw in the calculations, thanks to the contrast with the reluctance of the magnetic circuit difference.
On the one hand, electric motors convert the supplied electrical energy into mechanical energy. On the other hand, the electrical generator uses mechanical energy and subsequently changes it into electrical energy.
In both cases, at the moment when the stator and rotor energy exchange works at the same time, in order to produce a magnetic flux by means of copper coils that the two machines have In this process of converting energy, the air gap comes into play.
Inside the air gap, a magnetic field is formed, one of the coils is in charge of producing the flux which must move through the air gap. This must be crossed twice by each pole that contains the electrical machine for each phase.
One of its essential functions is to provide linearity to the magnetic circuit. It is also responsible for avoiding core saturation since it is in charge of distributing the flux dispersion manifested in an air gap to a large extent.
A medida que aumenta el entrehierro, asimismo aumenta la reluctancia, es decir, la resistencia que el material tiene en el momento en el que atraviesa el flujo magnético afectado por un campo magnético del aire. El cual, por la ley de OHM magnética, el flujo tendría que reducirse, al ser una fuerza que produce una intensidad de campo magnético constante.
A very important factor is that the greater the number of motor or generator poles, the more times the flux has to cross the air gap. Another very important factor is the monitoring of the air gap in electric motors and generators, otherwise, they would cause machine malfunctions.
Ferromagnetism is a property possessed by some materials which are attracted into the magnetic field. A ferromagnetic material is a material that has ferromagnetism which is attracted to magnets. Ferromagnetic elements are characterized by their magnetization which is supported by magnetic fields and remains magnetized even if the field is canceled.
In the same way, ferromagnetic minerals are attracted by a magnet, these minerals can be magnetized and become a magnet (natural or artificial) These types of materials can be magnetized quickly and retain their magnetization for a long period of time. In addition, one of the advantages they have is the ease with which the dipoles can be altered.
In 1907, Wess gained that knowledge when they examined the magnetic moments of atoms. According to the theory of Frenchman Pierre-Ernest Weiss ferromagnetic solid consists of a large number of small regions, or domains, in each of which all atomic or ionic magnetic moments are aligned. In a direction of uniform magnetization within a domain.
Ferromagnetism works by presenting this type of material to an intense magnetic field. Consequently, with this, we get an alignment in the same direction as the ferromagnetism core.
The materials with these characteristics areiron, cobalt, and nickel. Within these three the one that has more weight is iron, which response to the magnetic field that at the same time is being applied to it as well as to its internal configuration.
Ferromagnetism is referred to as the property of relative magnetic permeability greater than 1. The relative permeability can be known by the following fraction:
- μ = absolute permeability coefficient of a particular medium.
- μ0 = vacuum permeability
Materials have a limit temperature, which if exceeded couldlose their ferromagnetic properties. The temperature of these magnetic elements is called Curie temperature.
The applications of composite materials with ferromagnetic particles today are as:
Household appliances: they are found in kitchen appliances, whether induction hobs or frying pans.
Medical field: used to manufacture pacemakers, implants, and defibrillators.
Technological field: they are found in cell phone headsets that use electromagnets.
Industrial field: used in electric motors and transformers.
The first electro-permanent magnet was created in 1824 by the physicist William Sturgeon. This physicist connected a wire to the two ends of a battery, this wire was wound to an iron bar as we can see in the photo.
Later, the passage of time the electro-permanent magnet evolved into the magnet we know today.
An electro-permanent magnet or also known as direct current electromagnets are a type of magnet made of ferrous alloys that produce a constant field and intensity, in other words, the current is given due to the circulation of electrons moving from the pole (-) to the pole (+), these maintain the same polarity.
DC electromagnets are responsible for converting electric current into the mechanical current.
The electro-permanent magnet is used for the following characteristics:
As its name suggests, it has a direct current, i.e. it has an uninterruptible power supply.
It has a flat piece F1112 and a thickness of 3µ.
They have the capacity to maintain 35ºC of temperature.
The air gap between the center of the extractor and the rotor is zero.
If the magnet is a neodymium magnet, as this type of permanent magnet already has a high magnetic force, it does not require an electric current. However, in the case of an electric current, it will neutralize the force that the neodymium magnet already possesses from the beginning.
The operation of the electromagnets of direct current is due to its 24V power supply, at the moment in which we activate the current, a magnetic field is produced, where it concentrates on an iron armature helping to fix any type of fastening.
Electromagnets are activated directly in contact with the metal part. This type of electromagnet is predestined to offer a permanent and comfortable operation.
Applications that require a direct current to operate are televisions, computers, mobile phones..... On the other hand, like all electromagnets, they are used for electromagnetic brakes and clutches, as well as electric motors. DC electromagnets are used for applications that require manipulation of metal objects in industrial robotics, as they are required for positioning parts.
No.155-1, North Jingu Road
Yinzhou Investment & Business Industrial
Ningbo, PR China 315104
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20080 Milan
Tlf: +39 (02) 94 00 137
Tlf: +39 (02) 94 00 609
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08291 Ripollet (Barcelona)
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E-mail: contacto@imamagnets.com
