Glossary of magnetic terminology
How to navigate the world of neodymium magnets?
Welcome to our detailed glossary focused on the fascinating world of neodymium magnets. As a trusted leader in providing top-notch magnetic solutions, we know how crucial it is to have a reliable information about the concepts in this exceptional field. This glossary has been thoughtfully crafted to serve as an valuable source of information for all those interested who is keen on magnets – whether you are an experienced industry professional, a hobbyist, or someone simply curious the science of magnets.
In our glossary, you will find readable and comprehensive explanations of fundamental concepts and ideas related to neodymium magnets. From the basics of field mechanics and field intensity, to material characteristics and magnetic innovations, each definition has been crafted to expand your understanding and ease the comprehension of even the most complex ideas. If you are exploring industrial applications, performing DIY projects, or simply delving into magnetism, this glossary aims to support your learning.
Explore the amazing world of neodymium magnets with ease. Expand your knowledge, gain fresh perspectives, and realize the possibilities of these innovative materials, reading about and concepts that describe their operation and utility. Let this glossary your tool in delving into the dynamic landscape of magnetic technology.
Litera: A
The air gap is the space filled with air that separates a magnet from a ferromagnetic material. Increasing the 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 more efficient than isotropic 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 protective atmosphere 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 along the length of the magnet. This configuration is popular in ring-shaped and ball-shaped magnets. Formula: Bz = (Br/2) × [(L + 2z) / (L² + 4z²)0.5 - (L - 2z) / (L² + 4z²)0.5].
Litera: B
Magnetic induction B is the field intensity passing through a unit area. 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 graphical representation of the relationship between magnetic induction (B) and magnetizing force (H). It helps determine properties like coercivity. The hysteresis loop is essential in evaluating materials used in electric motors.
Remanent induction Bd is the residual magnetic field in a material after the magnetizing force 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 a coefficient describing magnetic permeability. Formula: Bd/Hd = (Br - Hd) / Hd. This is a key parameter in the design of magnetic circuits.
Bg represents the level of magnetic field in the air gap. It is a critical parameter in designing devices such as sensors and actuators. 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. Although it has been replaced by the MKSA (SI) system, C.G.S. is still relevant in magnetic data presentations. This system includes units for as well as length, mass, and time.
A closed circuit refers to a configuration where the magnetic flux forms a complete loop. It uses high-permeability materials to ensure continuity of magnetic field flow. They are critical in applications requiring controlled magnetic fields.
Coercive force, denoted as Hc, is the necessary strength to demagnetize a material. This parameter measures the durability of its magnetic properties. 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. It also affects magnetic stability under varying conditions.
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 offer magnetic stability.
Curie temperature is the point at which ferromagnetic materials lose their magnetic properties. Beyond this temperature, the material ceases to exhibit strong magnetic behavior. 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 weakening residual induction in a material. Methods include applying alternating magnetic fields, heating above the Curie temperature. 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 coercivity and remanent induction. This tool is vital for analyzing magnetic material characteristics.
Demagnetization force refers to the opposing magnetic field that reduces the magnetization of a material. This force allows for controlling the level of magnetization in materials.
A demagnetized material is one where all residual magnetization has been removed. This state is achieved through or other demagnetization techniques such as heating. Demagnetization is important in applications requiring neutral magnetic properties.
approximately 7.5 g/cm³, is one of the key parameters defining its magnetic properties. Density can be approximately determined 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 creating a counteracting magnetic field.
Diameter refers to the measured in a straight line across the surface of or other geometric shape. It is a critical parameter in designing magnetic systems.
Diametrically magnetized magnets have creating a circular magnetic field pattern. They are commonly used in applications requiring unique magnetic field configurations.
Dimensional tolerance specifies the range of variation in magnet size. It is crucial for precise fitting.
Dimensions refer to the such as length, width, height, or diameter of a magnet. Accurate dimensioning is key to ensuring the proper functionality of magnetic systems.
The direction of magnetization defines the orientation of magnetic domains. This is a critical feature that affects field interactions with other elements.
Domains are microscopic regions where creating localized magnetic fields. They can be altered by external magnetic fields, temperature, or stress.
Litera: E
Eddy currents are electrical currents induced 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. The strength of the magnetic field depends on the current. Electromagnets are applied in such as motors, generators, or MRI systems.
The energy product is an indicator of a magnet's ability to supply energy. It is calculated as the product of magnetic induction (Bd) and magnetizing force (Hd). Expressed in MGOe (Mega Gauss Oersteds) or kJ/m³, it is an essential measure for evaluating the performance and strength of magnets.
The energy product represents the maximum energy stored in a magnet. Magnets with higher energy products deliver better efficiency.
Litera: F
Ferrites are ceramic magnetic materials. Renowned for their high-frequency properties. Used in applications requiring low eddy current losses.
A ferromagnetic material is characterized by strong magnetic properties. In such materials, atoms generate a strong magnetic field. Examples include iron, nickel, cobalt. They are widely used due to their ability to retain magnetization.
Flux density, denoted as B, defines the strength of the magnetic field. Measured in Teslas (T) or Gauss (G), it is a crucial parameter for evaluating magnet performance.
A fluxmeter is used to measure magnetic induction (B). It employs various technologies such as to provide precise measurements. It is essential for diagnostics and design.
Litera: G
Gauss is named after German physicist Carl Friedrich Gauss. 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. Helpful in magnetic diagnostics.
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 oersteds (Oe) or kiloamperes per meter (kA/m), higher Hc values indicate greater magnetic stability.
Hd denotes the magnetic field strength required to achieve a specific remanent induction (Bd). Measured in various magnetic units.
A high field gradient magnet produces precisely controlled gradients. Applications include MRI, magnetic separation.
Hm represents a key parameter in magnetic system design. It is critical for designing systems requiring high magnetic fields.
A homogeneous field is characterized by constant strength and direction. It is crucial for applications requiring precise magnetic fields.
A horseshoe magnet has enhancing the field strength in that region. Popular in education, metal detection.
Net effective magnetizing force (Hs) refers to the field needed to fully magnetize a material to saturation. Measured in units of magnetic force.
The hysteresis graph, also called a permeameter, illustrates the magnetic characteristics of materials. It is used in quality control, energy loss analysis.
The hysteresis loop is a characteristic of magnetic materials. It provides information about the behavior of materials during magnetization cycles.
Hysteresis refers to a characteristic of magnetic materials. Hysteresis loss is a transformation of energy into heat. crucial for designing transformers and motors.
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 the effects of high temperatures, mechanical stress, or demagnetizing fields. They result in challenges in long-term magnet usage.
An isotropic material is independent of magnetic field orientation. 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. It provides a low magnetic resistance path for flux. 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 a graphical relationship between remanent induction (Bd) and demagnetizing force (Hd). useful for optimizing magnetic applications.
Lodestone is the first known natural magnet. Historically used for compasses.
Litera: M
A magnet is a material attracting or repelling other magnetic materials. widely used in electronics, motors, generators, and magnetic storage devices.
A magnetic assembly is designed to achieve specific magnetic properties. and magnetic levitation systems.
The magnetic axis is the preferred path of magnetic flux. essential for analyzing the magnet's behavior and interactions with other magnetic components.
A magnetic circuit is analogous to an electrical circuit. Comprises magnetic materials, air gaps, and other components.
Magnetic energy is the potential of the magnetic field to perform work. Important in applications like magnetic resonance imaging or magnetic generators.
A magnetic field (B) is a fundamental electromagnetic phenomenon. 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 a measure of the total magnetic field in a given region. Expressed in webers (Wb).
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.
Provides key data such as remanence and coercivity. 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 an imaginary curve representing the direction and shape of a magnetic field. lines form closed loops for most magnets.
A magnetic path refers to the route taken by magnetic flux in a magnetic circuit or system. minimizes magnetic losses.
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.
Magnetic saturation describes the maximum magnetic field intensity a material can achieve. This parameter is vital when selecting materials for high-field applications.
Magnetization refers to the process of aligning or inducing a magnetic field within a material. key to the function of magnets and magnetic devices.
It can be achieved using a magnetic field or electric current. The ability to magnetize is crucial in designing permanent magnets and electromagnets.
A magnetization curve, also called a B-H curve or demagnetization curve, represents the relationship between magnetic field strength (H) and magnetic induction (B). useful for selecting materials for specific applications.
Magnetized refers to the result of aligning magnetic moments in a specific direction. This state can be achieved through exposure to a magnetic field, contact with magnets, or electric current flow.
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 a substance exhibiting magnetic properties or influenced by a magnetic field. The magnetic behavior of a material depends on its atomic and molecular structure.
Maximum energy product, denoted as BHmax, represents the peak capability of a magnet to store and release magnetic energy.
The formula for BHmax is:
BHmax = B × H
Where:
B: Magnetic flux density (Tesla)
H: Magnetic field strength (A/m)
For a magnet with B = 1.2 T and H = 800 kA/m, BHmax equals 960 kJ/m³.
BHmax is a critical parameter for evaluating magnet performance, particularly in projects requiring maximum energy efficiency.
The formula for BHmax is:
BHmax = B × H
Where:
B: Magnetic flux density (Tesla)
H: Magnetic field strength (A/m)
For a magnet with B = 1.2 T and H = 800 kA/m, BHmax equals 960 kJ/m³.
BHmax is a critical parameter for evaluating magnet performance, particularly in projects requiring maximum energy efficiency.
Maximum operating temperature (Tmax) is a crucial parameter for applications in high-temperature environments. 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. 1 MGOe equals one million gauss-oersteds, making it a convenient unit for comparing magnet strength and performance in industrial applications.
A monopole refers to a hypothetical single magnetic pole existing independently as either a north or south magnetic pole. So far, monopoles have not been observed in nature.
Litera: N
N rating refers to a numerical designation, e.g., N35, N42, or N52, indicating the maximum energy product (BHmax). These ratings assist users in selecting appropriate magnets for specific applications.
The north pole is the pole that, when freely suspended, points toward the Earth's geographic North Pole. associated with the direction of outgoing magnetic field lines.
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. In this state, magnetic field lines cannot form a closed loop, leading to weakened magnetic fields.
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. The magnetism of these materials vanishes when the external field is removed, distinguishing them from ferromagnetic materials.
Paramagnetism is a property of materials weakly attracted to magnetic fields. The magnetism disappears once the external field is removed, due to the presence of unpaired electrons.
A permanent magnet is generates a persistent magnetic field without requiring an external magnetic field. used in electric motors, generators, magnetic storage devices, and speakers.
Permanent magnets generate a magnetic field without the need for external power. They are used in devices requiring a constant magnetic field, such as speakers, motors, and generators.
a characteristic that allows a material to support the formation of a magnetic field. High permeability enables efficient transmission of magnetic flux, critical for designing magnetic circuits.
Permeance, denoted by the symbol P, is a measure of a material's ability to conduct magnetic flux.
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.
indicates the slope of the operating line on the demagnetization curve. 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. Common coating materials include nickel, copper, epoxy, zinc, gold, and tin.
Polarity describes the orientation of the magnetic field in a neodymium magnet, which has two poles: north and south. plays a significant role in the design of magnet-based devices.
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: In the case where 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: In the case where 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
Rare earth metals are a group of chemical elements, such as neodymium, which are key components of neodymium magnets. form the basis of innovative technological solutions.
They are made from rare earth elements like neodymium, dysprosium, and praseodymium. Their high efficiency makes them indispensable in numerous applications.
indicates a material's ability to concentrate magnetic flux. is a crucial parameter in magnetic engineering.
Reluctance is a measure of the opposition a magnetic circuit presents to the flow of magnetic flux. 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.
Reluctance can be calculated using the formula:
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.
Understanding reluctance allows optimization of systems such as electromagnets, transformers, and electric motors.
Reluctance can be calculated using the formula:
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.
Understanding reluctance allows optimization of systems such as electromagnets, transformers, and electric motors.
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.
This occurs due to opposing magnetic fields generated by the magnets, causing them to repel each other. 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. Is a critical component in designing efficient magnetic circuits.
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.
The formula for shear force is:
Fs = F × tan(θ)
Where:
F: Pull force (N)
θ: Angle of the contact surface (rad)
For example, if F = 50 N and the angle θ = 30°, the shear force is approximately 28.9 N.
Shear force is a crucial factor in designing magnetic systems, particularly where high mechanical stability is required.
The formula for shear force is:
Fs = F × tan(θ)
Where:
F: Pull force (N)
θ: Angle of the contact surface (rad)
For example, if F = 50 N and the angle θ = 30°, the shear force is approximately 28.9 N.
Shear force is a crucial factor in designing magnetic systems, particularly where high mechanical stability is required.
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.
This process involves arranging magnets in series or parallel configurations, enhancing the magnetic field. Such arrangements enable stronger magnetic interactions and improved performance in various applications, such as magnetic separators, holders, or sensors.
Litera: T
Tesla is a unit of measurement for magnetic flux density, describing the strength and intensity of a magnetic field. The unit is named after Nikola Tesla, a renowned inventor and physicist whose work revolutionized electromagnetism.
Anisotropic magnets have a specific direction of magnetization, ensuring higher efficiency compared to isotropic magnets. Isotropic magnets are ideal for general applications due to their flexibility.
Litera: W
Named after Wilhelm Eduard Weber, a German physicist and pioneer of electromagnetic theory. Useful in analyzing magnet effectiveness in applications like generators, motors, and energy storage systems.
The weight of a neodymium magnet is an essential parameter 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).
Example: A magnet with a density of 7.5 g/cm³ and a volume of 10 cm³, the weight is:
m = 7.5 × 10 = 75 g.
Calculating the weight helps select the right magnet for specific applications.
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).
Example: A magnet with a density of 7.5 g/cm³ and a volume of 10 cm³, the weight is:
m = 7.5 × 10 = 75 g.
Calculating the weight helps select the right magnet for specific applications.