Glossary of magnetic terminology
How to navigate the world of neodymium magnets?
Hello to our detailed glossary dedicated to the fascinating world of neodymium magnets. As a leading expert in providing high-quality magnetic solutions, we know how crucial it is to have a solid knowledge about the terminology in this unique field. This glossary has been thoughtfully crafted to serve as an key source of information for everyone who is curious about magnets – regardless of whether you are an expert, a hobbyist, or someone simply curious the applications of magnets.
In our glossary, you will find readable and thorough explanations of important notions and subjects related to neodymium magnets. From the mechanisms behind magnetic functions and field intensity, to magnetization curves and magnetic innovations, each definition has been crafted to expand your understanding and simplify even the intricate ideas. Whether you are studying industrial applications, conducting scientific experiments, or simply delving into magnetism, this glossary aims to support your learning.
Explore the amazing world of neodymium magnets with ease. Broaden your understanding, uncover new insights, and unlock the potential of these indispensable materials, grasping definitions and ideas that describe their operation and utility. Use this glossary your partner in navigating the developing domain of magnetic technology.
Litera: A
The air gap is the distance filled with air that separates a magnet from another object. 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, such as neodymium magnets, has properties that vary with direction. Magnets with a preferred magnetization direction are more efficient than uniform magnets, but they can only be magnetized in one direction.
Annealing is a heat treatment process in magnetic materials. It is performed at high temperatures, usually in a vacuum to prevent material degradation. Annealing enhances the magnetic properties and allows for better performance in applications.
Axial magnetization means that the magnetic poles are distributed along the axis of the magnet, and the magnetic field lines run along the length of the magnet. This configuration is popular in cylindrical 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 amount of magnetic flux passing through a unit area. It is measured or gauss. 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 coercivity. The hysteresis loop is a fundamental tool in evaluating materials used in transformers.
Remanent induction Bd is the remaining magnetization 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 ratio of remanent induction to demagnetizing force. 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 important factor 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 one of the oldest measurement systems. 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 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 continuity of magnetic field flow. Such circuits are essential in applications requiring controlled magnetic fields.
Coercive force, denoted as Hc, is the necessary strength to reduce magnetic induction to zero. 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 ability to maintain its magnetic properties. 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 transition to a paramagnetic state. 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 weakening residual induction in a material. Methods include applying alternating magnetic fields, heating above the Curie temperature. This process is essential in applications requiring precise control of magnetization.
The demagnetization curve illustrates the relationship between magnetic induction (B) and magnetizing force (H). It reveals the material's hysteresis characteristics, including coercivity and remanent induction. This tool is commonly used in designing magnetic circuits.
Demagnetization force refers to the opposing magnetic field that induces demagnetization. This force allows for controlling the level of magnetization in materials.
A demagnetized material is one where remanent induction has been reduced to zero. This state is achieved through applying alternating magnetic fields. 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 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.
Understanding density allows for better parameter selection in various applications.
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.
Understanding density allows for better parameter selection in various applications.
Diamagnetic materials exhibit weak repulsion to magnetic fields. When exposed to an external field, they generate an opposing field. This behavior results from creating a counteracting magnetic field.
Diameter refers to the distance between the farthest points across the surface of or other geometric shape. It is a critical parameter in designing magnetic systems.
Diametrically magnetized magnets have poles located on opposite sides of the diameter. They are commonly used in applications requiring radial or rotational interactions.
Dimensional tolerance specifies the range of variation in magnet size. It is crucial for integrating magnetic components into systems.
Dimensions refer to the measurable physical properties of a magnet. Accurate dimensioning 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 field interactions with other elements.
Domains are zones within a magnetic material where creating localized magnetic fields. They can be altered by physical and mechanical factors.
Litera: E
Eddy currents are circulating currents created in conductive materials when exposed to fluctuations in the magnetic field. They cause energy losses, heating, or resistive effects. 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 multiplication of two parameters from the demagnetization curve. Expressed in various units, it is an essential measure for evaluating their efficiency in applications.
Measured as the product of the material's remanence and coercivity. 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 its ability to amplify magnetic flux. In such materials, atoms align parallel under an external magnetic field. Examples include iron, nickel, cobalt. 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 Teslas (T) or Gauss (G), it is a crucial parameter for designing magnetic systems.
A fluxmeter is used to measure magnetic induction (B). It employs various technologies such as the Hall effect or rotating coil techniques. It is a critical engineering tool.
Litera: G
Gauss is named after German physicist Carl Friedrich Gauss. One Gauss (G) equals 10^-4 Tesla (T). A historically popular unit.
A Gauss meter is a device for measuring magnetic field strength. It uses Hall effect sensors. It is used in many branches of engineering and science.
The Gilbert is a unit of magnetomotive force (mmf). 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
A Hall sensor operates on the principle of the Hall effect, which involves inducing a voltage in a conductor in the presence of a magnetic field. These devices play a crucial role in industrial automation and precision measurements.
Coercive force (Hc) represents the magnetic field strength needed to reduce a material's residual induction (Br) to zero. Expressed in oersteds (Oe) or kiloamperes per meter (kA/m), higher Hc values indicate resistance to external influences.
Hd denotes the magnetic field strength required to achieve a specific remanent induction (Bd). Measured in oersteds (Oe) or kiloamperes per meter (kA/m).
A high field gradient magnet produces strong and rapidly changing magnetic fields. 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 a lack of intensity variations over a given area. It is crucial for applications requiring precise magnetic fields.
A horseshoe magnet has enhancing the field strength in that region. and applications requiring focused magnetic fields.
Net effective magnetizing force (Hs) refers to an essential parameter for analyzing the magnetic properties of materials. Measured in oersteds (Oe) or kiloamperes per meter (kA/m).
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 the behavior of materials during magnetization cycles.
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 distance between the inner surfaces of an object. 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). critical in characterizing magnetic materials.
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 an accessory preventing demagnetization of magnets. 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). Helps evaluate magnetic material behavior and stability.
Lodestone is the first known natural magnet. possesses unique properties due to its magnetic domain alignment.
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 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 a path through which magnetic flux flows. 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 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. Expressed in webers (Wb).
Magnetic flux density, denoted as B, is a parameter describing the intensity of the magnetic field at a specific location. It represents the amount of magnetic flux passing through a unit area.
The equation for it is:
B = Φ / A
Where:
B: Magnetic flux density (Tesla, Gauss)
Φ: Magnetic flux (Weber)
A: Surface area (m²)
For example, with a magnetic flux of 0.01 Weber and an area of 0.1 m², the magnetic flux density is 0.1 Tesla.
A high B value indicates a stronger magnetic field, essential in industrial and medical applications.
The equation for it is:
B = Φ / A
Where:
B: Magnetic flux density (Tesla, Gauss)
Φ: Magnetic flux (Weber)
A: Surface area (m²)
For example, with a magnetic flux of 0.01 Weber and an area of 0.1 m², the magnetic flux density is 0.1 Tesla.
A high B value indicates a stronger magnetic field, essential in industrial and medical applications.
Provides key data such as remanence and coercivity. Ideal for applications in transformers and electric motors.
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. 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. 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.
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. 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 a graphical depiction of a material's magnetic properties. useful for selecting materials for specific applications.
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. The magnetic behavior of a material depends on its atomic and molecular structure.
Maximum energy product, denoted as BHmax, is a measure of the maximum energy a magnet can deliver per unit volume.
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. Ensures material stability and performance under specified conditions.
Maxwell is represents the amount of magnetic flux passing through a surface area of one square centimeter in a magnetic field of one gauss. critical for historical and scientific magnetic applications.
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 theoretical concept explored in physics, particularly particle physics. In reality, magnetic poles always occur in pairs, but monopoles are theorized in certain models.
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 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. In this state, magnetic field lines cannot form a closed loop, leading to weakened magnetic fields.
Orientation refers to the alignment or positioning of a magnet, magnetic material, or magnetic component relative to a reference axis. 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. The magnetism disappears once the external field is removed, due to the presence of unpaired electrons.
A permanent magnet is a material or object that retains its magnetic properties indefinitely. It is made from materials with strong magnetic properties, such as iron, nickel, or cobalt alloys.
They are made from materials with high magnetic retention. Their durability and stability make them indispensable in many industrial applications.
Magnetic permeability is a property of a material determining its ability to conduct magnetic flux. the value of permeability depends on the chemical composition and structure of the material.
Permeance, denoted by the symbol P, is a measure of a material's ability to conduct magnetic flux.
Permeance can be calculated using the formula:
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.
High permeability is crucial for enhancing the efficiency of magnetic systems.
Permeance can be calculated using the formula:
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.
High permeability is crucial for enhancing the efficiency of magnetic systems.
The permeance coefficient is the ratio of remanence (Br) to coercive force (Hd) in a magnetic material. is important for designing efficient magnetic circuits.
Plating or coating refers to the process of applying a protective layer to the surface of neodymium 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, also known as holding force, describes the force required to separate a magnet from a ferromagnetic surface. 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. Due to their high magnetic strength, they are used in industries, electronics, and consumer technologies.
They are made from rare earth elements like neodymium, dysprosium, and praseodymium. Their high efficiency makes them indispensable in numerous applications.
Relative permeability is a measure of how easily a material can be magnetized compared to a vacuum. is a crucial parameter in magnetic engineering.
Reluctance is a measure of the opposition a magnetic circuit presents to the flow of magnetic flux. The design and geometry of the magnet and surrounding materials affect reluctance and the efficiency of magnetic circuits.
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. Allows for assessing the long-term stability and suitability of magnets for various applications.
Repelling refers to the phenomenon where like poles of neodymium magnets (e.g., north to north) exert a force that pushes them apart. Is important in designing systems where avoiding contact between magnets is necessary.
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 shift 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.
This parameter plays a key role in applications such as magnetic mounts or sliding mechanisms.
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.
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.
This process involves arranging magnets in series or parallel configurations, enhancing the magnetic field. 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. Useful in analyzing magnet effectiveness in applications like generators, motors, and energy storage systems.
The weight of a neodymium magnet is a critical factor influencing its applications. It can be simply determined 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.
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).
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.
Knowing the weight is crucial in projects where balance between mass and magnetic force is important.