Glossary of magnetic terminology
How to navigate the world of neodymium magnets?
Welcome to our extensive glossary dedicated to the fascinating world of neodymium magnets. As a recognized supplier in providing high-quality magnetic solutions, we know how important it is to have a solid knowledge about the basic notions in this specialized field. This glossary has been carefully developed to serve as an invaluable source of information for anyone who is interested in magnets – whether or not you are an expert, a hobbyist, or an enthusiast the science of magnets.
In our glossary, you will find readable and detailed explanations of important notions and subjects related to neodymium magnets. From the basics of field mechanics and field intensity, to magnetization curves and material grades, each definition has been designed to expand your understanding and simplify even the most complex ideas. If you are researching industrial applications, conducting scientific experiments, or simply delving into magnetism, this glossary aims to support your learning.
Discover the captivating world of neodymium magnets with confidence. Expand your knowledge, gain fresh perspectives, and discover the applications of these exceptional materials, understanding terms and concepts that describe their operation and utility. Consider this glossary as your tool in exploring the developing domain of magnetic technology.
Litera: A
The air gap is the space filled with air that separates a magnet from a ferromagnetic material. A larger air gap weakens the magnetic field. Formula: B = μ0(H - M), where:
B - magnetic induction,
μ0 - permeability of free space,
H - magnetic field strength,
M - magnetization.
B - magnetic induction,
μ0 - permeability of free space,
H - magnetic field strength,
M - magnetization.
An anisotropic material, e.g., neodymium magnets, has properties dependent on orientation. Magnets with a preferred magnetization direction are stronger than uniform magnets, but they can only be magnetized along a specific axis.
Annealing is a method for relieving internal stresses in magnetic materials. It is performed under controlled conditions, usually in a vacuum to prevent material degradation. Annealing improves the structure and allows for better performance in applications.
Axial magnetization means that the magnetic poles are distributed along the axis of the magnet, and the lines of force run parallel to its axis. This configuration is popular in cylindrical and spherical magnets. Formula: Bz = (Br/2) × [(L + 2z) / (L² + 4z²)0.5 - (L - 2z) / (L² + 4z²)0.5].
Litera: B
Magnetic induction B is the amount of magnetic flux passing through a surface. It is measured in teslas. Formula: B = μ0(H + M), where:
μ0 - permeability of free space,
H - applied magnetic field,
M - magnetization.
μ0 - permeability of free space,
H - applied magnetic field,
M - magnetization.
The hysteresis loop is a chart of the relationship between magnetic induction (B) and field strength. It helps determine properties like magnetic energy loss. The hysteresis loop is essential in evaluating materials used in electric motors.
Remanent induction Bd is the remaining magnetization in a material after the external magnetic field is removed. It is measured or gauss and represents the material's ability to retain magnetism.
The slope of the operating line, denoted as Bd/Hd, is the ratio of remanent induction to demagnetizing force. Formula: Bd/Hd = (Br - Hd) / Hd. This is a key parameter in the design of electromagnetic systems.
Bg represents the average magnetic induction in the air gap. It is a important factor in designing devices based on magnetic circuits. Formula: Bg = Φ / A, where:
Φ - magnetic flux,
A - air gap area.
Φ - magnetic flux,
A - air gap area.
Litera: C
The C.G.S. system of units is primarily used in magnetism for describing material properties. Despite being succeeded by the MKSA (SI) system, C.G.S. is still relevant in magnetic data presentations. This system includes units for magnetizing force and magnetic induction.
A closed circuit refers to a configuration where the magnetic flux forms a complete loop. It uses high-permeability materials to ensure minimized flux losses. They are critical in applications requiring controlled magnetic fields.
Coercive force, denoted as Hc, is the field intensity required to reduce magnetic induction to zero. This parameter measures the material's resistance to demagnetization. Formula: Hc = -M/χ, where:
M - magnetization,
χ - magnetic susceptibility.
M - magnetization,
χ - magnetic susceptibility.
High coercivity indicates the durability of a material's magnetic properties. This parameter is critical in designing permanent magnets for motors and generators.
Intrinsic coercivity, denoted as Hci or iHc, represents the material's resistance to losing magnetization. It measures the demagnetizing force required to reduce internal magnetization to zero. Materials with high coercivity exhibit long-lasting magnetic characteristics.
Curie temperature is the point at which ferromagnetic materials lose their magnetic properties. Beyond this temperature, the magnetic structure becomes disordered. Formula: Tc = (2kB / μ0) × J02 / χ, where:
kB - Boltzmann constant,
J0 - magnetic moment.
kB - Boltzmann constant,
J0 - magnetic moment.
Litera: D
Demagnetization refers to the process of reducing or eliminating magnetization. Methods include or employing demagnetization techniques such as degaussing. This process is essential in applications requiring complete removal of magnetic properties.
The demagnetization curve illustrates the relationship through cycles of magnetization and demagnetization. It reveals the material's hysteresis characteristics, including stability of magnetic properties. This tool is commonly used in designing magnetic circuits.
Demagnetization force refers to the external magnetic field that reduces the magnetization of a material. This force allows for manipulating magnetic properties.
A demagnetized material is one where all residual magnetization has been removed. This state is achieved through applying alternating magnetic fields. Demagnetization is important in eliminating unwanted magnetic effects.
approximately 7.5 g/cm³, is one of the key parameters defining its magnetic properties. Density can be easily calculated using the formula:
ρ = m / V, where:
ρ - density (in g/cm³ or kg/m³),
m - mass of the magnet (in grams or kilograms),
V - volume of the magnet (in cm³ or m³).
Example: For a magnet with a mass of 150 g and a volume of 20 cm³, the density is:
ρ = 150 / 20 = 7.5 g/cm³.
Knowing the density helps predict the magnet's strength and durability.
ρ = m / V, where:
ρ - density (in g/cm³ or kg/m³),
m - mass of the magnet (in grams or kilograms),
V - volume of the magnet (in cm³ or m³).
Example: For a magnet with a mass of 150 g and a volume of 20 cm³, the density is:
ρ = 150 / 20 = 7.5 g/cm³.
Knowing the density helps predict the magnet's strength and durability.
Diamagnetic materials exhibit no permanent magnetic moment. When exposed to an external field, they generate an opposing field. This behavior results from induced currents within the material.
Diameter refers to the distance between the farthest points across the surface of or other geometric shape. It is a critical parameter in ensuring precise component alignment.
Diametrically magnetized magnets have creating a circular magnetic field pattern. They are particularly useful in applications requiring unique magnetic field configurations.
Dimensional tolerance specifies the acceptable deviation from specified dimensions. It is crucial for precise fitting.
Dimensions refer to the measurable physical properties of a magnet. Precision in measurements is essential for system design.
The direction of magnetization defines the path along which the magnetic field is established. This is a critical feature that affects the material's magnetic behavior.
Domains are zones within a magnetic material where creating localized magnetic fields. They can be altered by external magnetic fields, temperature, or stress.
Litera: E
Eddy currents are circulating currents created in conductive materials when exposed to fluctuations in the magnetic field. They cause efficiency issues. The use of optimized designs minimizes their impact and enhances performance.
An electromagnet is a magnet created by passing an electric current through a conductor. Adjusting the current allows control over the magnetic field. Electromagnets are applied in industries and technologies.
The energy product is an indicator of a magnet's ability to supply energy. It is calculated as the multiplication of two parameters from the demagnetization curve. Expressed in various units, it is a critical parameter for evaluating their efficiency in applications.
The energy product represents the maximum energy stored in a magnet. This parameter is essential in evaluating the performance and strength of a magnet in industrial applications.
Litera: F
Ferrites are ceramic magnetic materials. They combine low electrical conductivity with high magnetic permeability. Used in transformers, inductors, and telecommunication devices.
A ferromagnetic material is characterized by strong magnetic properties. In such materials, atoms align parallel under an external magnetic field. Examples include and their alloys. These materials are fundamental due to their ability to retain magnetization.
Flux density, denoted as represents the amount of flux passing through a unit area. Measured in standard magnetic units, it is a crucial parameter for evaluating magnet performance.
A fluxmeter is used to quantify the magnetic field strength. It employs various technologies such as the Hall effect or rotating coil techniques. It is essential for diagnostics and design.
Litera: G
Gauss is a unit of magnetic induction. One Gauss (G) equals a smaller scale of magnetic induction. Commonly used in laboratory applications.
A Gauss meter is a instrument used to determine induction at points in space. It uses Hall effect sensors. It is used in many branches of engineering and science.
The Gilbert is named after William Gilbert, a pioneer in magnetic research. One Gilbert represents an older measure now replaced by ampere-turns (At) in the SI system.
The grade of a magnet refers to its magnetic properties, such as BHmax or Hc. Higher grades offer greater resistance to temperatures and demagnetizing forces.
Litera: H
Used for measuring magnetic fields and detecting position. These devices play a crucial role in industrial automation and precision measurements.
Coercive force (Hc) represents a measure of a material's resistance to demagnetization. Expressed in SI units, higher Hc values indicate greater magnetic stability.
Hd denotes the force needed to magnetize a material and retain that state after the field is removed. Measured in various magnetic units.
A high field gradient magnet produces precisely controlled gradients. Applications include and scientific research requiring advanced field parameters.
Hm represents the maximum applied magnetic field strength before a material reaches saturation. It is critical for assessing stability and operational limits of magnetic components.
A homogeneous field is characterized by constant strength and direction. It is such as spectroscopy or device calibration.
A horseshoe magnet has enhancing the field strength in that region. Popular in education, metal detection.
Net effective magnetizing force (Hs) refers to an essential parameter for analyzing the magnetic properties of materials. Measured in units of magnetic force.
The hysteresis graph, also called a permeameter, illustrates the magnetic characteristics of materials. It is used in and optimizing magnetic designs.
The hysteresis loop is a characteristic of magnetic materials. It provides information about energy losses, coercivity, and energy storage capacity.
Hysteresis refers to a characteristic of magnetic materials. Hysteresis loss is the energy lost as heat during magnetization and demagnetization cycles. Minimizing hysteresis loss improves the efficiency of magnetic systems.
Litera: I
Inner diameter (ID) refers to the internal dimension of a hollow object, such as a magnet, tube, or ring. It is an essential parameter in magnetic circuit design.
Magnetic induction (B) represents the amount of magnetic flux passing through a unit area. It is measured in Teslas (T) or Gauss (G). Essential for designing and analyzing magnetic systems.
Irreversible losses refer to a permanent reduction in a material's magnetization. They result in a decrease in magnetic properties and performance.
An isotropic material exhibits the same magnetic properties in all directions. Often compared to anisotropic materials with direction-dependent properties.
Litera: K
A keeper is a soft iron or ferromagnetic element placed on or between the poles of a permanent magnet. helps maintain the magnet's strength. Used primarily with historical magnet models.
Kilogauss (kG) is a unit used to express magnetic induction or flux density. 1 kilogauss = 1000 Gauss. and industrial sectors requiring strong magnetic fields.
Litera: L
The load line represents the operating points of a magnetic material on the demagnetization curve. useful for optimizing magnetic applications.
Lodestone is the first known natural magnet. possesses unique properties due to its magnetic domain alignment.
Litera: M
A magnet is an object producing a magnetic field with magnetic poles. Can be natural, like lodestone, or artificial, such as neodymium.
A magnetic assembly is a system comprising various magnetic components. and magnetic levitation systems.
The magnetic axis is an imaginary line within a magnet where the magnetic field is most concentrated or intense. It connects the poles of the magnet and defines the orientation of its magnetic field.
A magnetic circuit is analogous to an electrical circuit. key to designing magnetic devices.
Magnetic energy is the potential of the magnetic field to perform work. related to the strength of the magnetic field and the volume of space it occupies.
A magnetic field (B) is an area where magnetic materials or electric charges experience a magnetic force. created by magnets or electric currents.
Magnetic field strength (H) is the intensity of the magnetic field in a circuit. expressed in amperes per meter (A/m).
Magnetic flux is the number of magnetic field lines passing through a specific area. key in analyzing magnetic circuits and induction phenomena.
Magnetic flux density, denoted as B, is a measure of the strength or concentration of a magnetic field. It represents the number of magnetic field lines intersecting a surface.
It is expressed by the formula:
B = Φ / A
Where:
B: Magnetic flux density (Tesla, Gauss)
Φ: Magnetic flux (Weber)
A: Surface area (m²)
If the area is 0.05 m² and the magnetic flux is 0.002 Weber, the resulting flux density is 0.04 Tesla.
Magnetic flux density is critical for designing devices like motors, generators, or magnetic sensors.
It is expressed by the formula:
B = Φ / A
Where:
B: Magnetic flux density (Tesla, Gauss)
Φ: Magnetic flux (Weber)
A: Surface area (m²)
If the area is 0.05 m² and the magnetic flux is 0.002 Weber, the resulting flux density is 0.04 Tesla.
Magnetic flux density is critical for designing devices like motors, generators, or magnetic sensors.
The hysteresis loop illustrates the behavior of magnetic materials during cycles of magnetization and demagnetization. Materials with a narrower loop have lower energy losses.
Magnetic induction measures the amount of magnetic flux passing through a unit area. Higher induction values indicate stronger magnetic fields.
A magnetic line of force, also known as a magnetic field line, is the path showing how magnetic poles would move within the field. The density of field lines reflects the strength of the field at various locations.
A magnetic path refers to a configuration involving magnetic materials, air gaps, and other elements. A well-designed path ensures efficient magnetic energy transmission.
Magnetic permeability defines a material's ability to conduct magnetic flux. Materials with high permeability are more effective at concentrating magnetic fields.
Every magnet has a north and south pole. Understanding pole interactions is crucial in designing magnetic systems.
Beyond saturation, further increases in the external field do not enhance magnetization. It is also significant in designing magnetic circuits.
Magnetization refers to the process of aligning or inducing a magnetic field within a material. It can be achieved by exposure to a magnetic field, electric current flow, or contact with other magnets.
It can be achieved using a magnetic field or electric current. Control over the magnetization process enables achieving optimal parameters.
A magnetization curve, also called a B-H curve or demagnetization curve, represents the relationship between magnetic field strength (H) and magnetic induction (B). Provides critical insights into material characteristics, saturation, and magnetic stability.
Magnetized refers to the result of aligning magnetic moments in a specific direction. Magnetized materials exhibit magnetic properties and can attract or repel other magnetic materials.
Magnetomotive force (mmf) is a measure of the difference in magnetic potential. Analogous to electromotive force (EMF) in electrical circuits.
In magnetism, material refers to classified as ferromagnetic, paramagnetic, or diamagnetic. Ferromagnetic materials like iron can be permanently magnetized.
Maximum energy product, denoted as BHmax, represents the peak capability of a magnet to store and release magnetic energy.
It is calculated using the equation:
BHmax = B × H
Where:
B: Magnetic flux density (Tesla)
H: Magnetic field strength (A/m)
For example, a magnet with B = 1 T and H = 600 kA/m achieves a BHmax of 600 kJ/m³.
High BHmax values are characteristic of neodymium magnets, making them indispensable for advanced industrial applications.
It is calculated using the equation:
BHmax = B × H
Where:
B: Magnetic flux density (Tesla)
H: Magnetic field strength (A/m)
For example, a magnet with B = 1 T and H = 600 kA/m achieves a BHmax of 600 kJ/m³.
High BHmax values are characteristic of neodymium magnets, making them indispensable for advanced industrial applications.
Maximum operating temperature (Tmax) is the highest temperature at which a magnetic material can operate without significant degradation or loss of magnetic properties. Temperatures exceeding Tmax may result in material demagnetization.
Maxwell is represents the amount of magnetic flux passing through a surface area of one square centimeter in a magnetic field of one gauss. This unit is used in the CGS system and corresponds to 10^−8 webers (Wb).
Mega Gauss Oersteds (MGOe) is a unit used to express the maximum energy product (BHmax) of permanent magnets. This unit helps assess the magnetic potential of magnets in complex magnetic circuits.
A monopole refers to a theoretical concept explored in physics, particularly particle physics. So far, monopoles have not been observed in nature.
Litera: N
N rating refers to the classification of neodymium magnets based on their magnetic properties and performance. Higher N ratings correspond to stronger magnets with superior magnetic properties.
The north pole is one of the two fundamental magnetic poles of a magnet. The north pole of a magnet attracts the south pole of another magnet, generating magnetic attraction.
Litera: O
Oersted is named after Hans Christian Oersted, who discovered the relationship between electric currents and magnetic fields. mainly used in the CGS system.
An open circuit refers to a condition where a magnetic circuit is not closed or complete. open circuits may occur due to air gaps or insufficient magnetic materials.
Orientation refers to determines the direction and distribution of the magnetic field or flux. can significantly affect magnet interactions and circuit performance.
Litera: P
Paramagnetic materials are substances that exhibit paramagnetism and are weakly attracted to magnetic fields. examples include aluminum, manganese, and oxygen.
Paramagnetism is a property of materials weakly attracted to magnetic fields. examples include aluminum, platinum, and oxygen.
A permanent magnet is a material or object that retains its magnetic properties indefinitely. used in electric motors, generators, magnetic storage devices, and speakers.
They are made from materials with high magnetic retention. Their durability and stability make them indispensable in many industrial applications.
a characteristic that allows a material to support the formation of a magnetic field. the value of permeability depends on the chemical composition and structure of the material.
Permeance, denoted by the symbol P, describes the ease with which magnetic flux can flow through a specific magnetic circuit.
The mathematical formula for permeance is expressed as:
P = (μ × A) / l
Where:
μ: Magnetic permeability of the material (H/m)
A: Cross-sectional area of the magnetic path (m²)
l: Length of the magnetic path (m)
For a material with μ = 4π × 10⁻⁷ H/m, A = 0.01 m², and l = 0.1 m, permeance is 1.26 × 10⁻⁵ H.
Permeance is a key parameter in designing magnetic circuits, especially in applications requiring minimal magnetic losses.
The mathematical formula for permeance is expressed as:
P = (μ × A) / l
Where:
μ: Magnetic permeability of the material (H/m)
A: Cross-sectional area of the magnetic path (m²)
l: Length of the magnetic path (m)
For a material with μ = 4π × 10⁻⁷ H/m, A = 0.01 m², and l = 0.1 m, permeance is 1.26 × 10⁻⁵ H.
Permeance is a key parameter in designing magnetic circuits, especially in applications requiring minimal magnetic losses.
The permeance coefficient is the ratio of remanence (Br) to coercive force (Hd) in a magnetic material. This coefficient impacts magnetic stability and parameters such as the energy product (BHmax) in magnetic circuits.
Provides protection against corrosion, oxidation, and demagnetization, enhancing the durability of magnets. Thanks to coatings, magnets can be used in harsh environmental conditions.
like poles repel each other, while opposite poles attract. Understanding the polarity of magnets is crucial for their proper application and alignment in various magnetic systems.
these poles determine the direction of magnetic force and interactions between magnets. define how magnets behave in external fields.
Pull force, sometimes referred to as gripping force, describes a magnet's ability to maintain attachment. It can be approximately calculated using the formula:
F = B² × A / (2 × μ₀), where:
F - Pull force (in newtons, N).
B - Magnetic flux density at the magnet's surface (in teslas, T).
A - Contact area of the magnet with the material (in m²).
μ₀ - Permeability of free space (4π × 10⁻⁷ H/m).
Example: If the magnetic flux density is 1.2 T, and the magnet's contact area is 0.005 m², the pull force is:
F = (1.2)² × 0.005 / (2 × 4π × 10⁻⁷) ≈ 572 N.
F = B² × A / (2 × μ₀), where:
F - Pull force (in newtons, N).
B - Magnetic flux density at the magnet's surface (in teslas, T).
A - Contact area of the magnet with the material (in m²).
μ₀ - Permeability of free space (4π × 10⁻⁷ H/m).
Example: If the magnetic flux density is 1.2 T, and the magnet's contact area is 0.005 m², the pull force is:
F = (1.2)² × 0.005 / (2 × 4π × 10⁻⁷) ≈ 572 N.
Litera: R
these magnets are known for their exceptional magnetic properties and wide applications. form the basis of innovative technological solutions.
Rare earth magnets, such as neodymium, are known for their exceptional magnetic strength. These magnets are used in industries, medicine, and electronics where strong magnetic fields are required.
indicates a material's ability to concentrate magnetic flux. Neodymium magnets exhibit high relative permeability, enabling efficient design of magnetic circuits.
the magnetic equivalent of electrical resistance in current circuits. is a significant parameter in evaluating the effectiveness of magnetic systems.
Magnetic resistance, denoted by the symbol R, measures a magnetic circuit's opposition to magnetic flux.
The mathematical formula for reluctance is:
R = l / (μ × A)
Where:
R: Magnetic resistance (1/H)
l: Length of the magnetic path (m)
μ: Magnetic permeability of the material (H/m)
A: Cross-sectional area of the magnetic path (m²)
For example, with l = 0.2 m, μ = 4π × 10⁻⁷ H/m, and A = 0.01 m², the reluctance is approximately 1.59 × 10⁶ 1/H.
Reluctance is analogous to electrical resistance in DC circuits, making it a key parameter in designing magnetic circuits.
The mathematical formula for reluctance is:
R = l / (μ × A)
Where:
R: Magnetic resistance (1/H)
l: Length of the magnetic path (m)
μ: Magnetic permeability of the material (H/m)
A: Cross-sectional area of the magnetic path (m²)
For example, with l = 0.2 m, μ = 4π × 10⁻⁷ H/m, and A = 0.01 m², the reluctance is approximately 1.59 × 10⁶ 1/H.
Reluctance is analogous to electrical resistance in DC circuits, making it a key parameter in designing magnetic circuits.
Residual magnetism indicates the magnet's ability to retain its magnetic properties over time. It is a key parameter in evaluating the strength and performance of the magnet.
Repelling refers to the phenomenon where like poles of neodymium magnets (e.g., north to north) exert a force that pushes them apart. The repulsive force is proportional to the magnetic strength and distance between the magnets.
The return path in a magnetic circuit involving neodymium magnets refers to the route through which the magnetic flux travels to complete the magnetic circuit. By designing an effective return path, system efficiency can be maximized, and magnetic losses minimized.
Litera: S
Shearing force, denoted by the symbol Fs, refers to the force required to displace a magnet along the contact surface in a direction parallel to the contact plane.
Shear force can be calculated using the formula:
Fs = F × tan(θ)
Where:
F: Pull force (N)
θ: Angle of the contact surface (rad)
The greater the angle, the higher the force required to move the magnet.
This parameter plays a key role in applications such as magnetic mounts or sliding mechanisms.
Shear force can be calculated using the formula:
Fs = F × tan(θ)
Where:
F: Pull force (N)
θ: Angle of the contact surface (rad)
The greater the angle, the higher the force required to move the magnet.
This parameter plays a key role in applications such as magnetic mounts or sliding mechanisms.
The south pole is one of the two fundamental magnetic poles of a magnet. The south pole of a magnet attracts the north pole of another magnet, demonstrating magnetic attraction.
Stacking refers to the practice of combining multiple neodymium magnets to create an assembly with increased overall magnetic strength. Stacking magnets is commonly employed in applications requiring high magnetic strength.
Litera: T
Tesla is a unit of measurement for magnetic flux density, describing the strength and intensity of a magnetic field. In practice, tesla is used to evaluate magnet performance and design precise magnetic systems.
Isotropic magnets can be magnetized in any direction, making them versatile. Anisotropic magnets are used in precise devices like electric motors.
Litera: W
Weber is the unit of magnetic flux, representing the total number of magnetic field lines passing through a specific area. It is a critical parameter for evaluating and quantifying magnetic fields and flux in neodymium magnets.
The weight of a neodymium magnet is a critical factor influencing its applications. It can be easily calculated based on its density and volume using the formula:
m = ρ × V, where:
m - mass of the magnet (in grams or kilograms).
ρ - density of the magnet (typically 7.5 g/cm³).
V - volume of the magnet (in cm³ or m³).
For a magnet with a typical density of 7.5 g/cm³ and a volume of 10 cm³, the weight is:
m = 7.5 × 10 = 75 g.
Knowing the weight is crucial in projects where balance between mass and magnetic force is important.
m = ρ × V, where:
m - mass of the magnet (in grams or kilograms).
ρ - density of the magnet (typically 7.5 g/cm³).
V - volume of the magnet (in cm³ or m³).
For a magnet with a typical density of 7.5 g/cm³ and a volume of 10 cm³, the weight is:
m = 7.5 × 10 = 75 g.
Knowing the weight is crucial in projects where balance between mass and magnetic force is important.