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 leading expert in providing high-quality magnetic solutions, we know how crucial it is to have a deep understanding about the basic notions in this exceptional field. This glossary has been carefully developed to serve as an invaluable source of information for everyone who is curious about magnets – whether you are an expert, a hobbyist, or an enthusiast the applications of magnets.
In our glossary, you will find readable and detailed explanations of key terms and topics related to neodymium magnets. From the principles of magnetic fields and flux density, to behavioral trends and magnetic innovations, each definition has been created with the aim of expand your understanding and ease the comprehension of even the most complex ideas. Whether you are researching industrial applications, performing DIY projects, or simply curious magnetism, this glossary will be your reliable guide.
Discover the captivating world of neodymium magnets with ease. Broaden your understanding, uncover new insights, and discover the applications of these indispensable materials, grasping definitions and theories that influence their versatility and utility. Consider this glossary as your guide in exploring the dynamic landscape of magnetic technology.
Litera: A
The air gap is the distance or another non-magnetic material that separates a magnet from another object. A larger air gap weakens the attractive force. 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 isotropic magnets, but they can only be magnetized along a specific axis.
Annealing is a heat treatment process in magnetic materials. It is performed under controlled conditions, usually in a protective atmosphere 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 commonly used 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 - external magnetic field strength,
M - magnetization.
μ0 - permeability of free space,
H - external magnetic field strength,
M - magnetization.
The hysteresis loop is a graphical representation of the relationship between magnetic induction (B) and field strength. It helps determine properties like magnetic energy loss. The hysteresis loop is a fundamental tool in evaluating materials used in electric motors.
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 electromagnetic systems.
Bg represents the level of magnetic field 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 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 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 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. 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 acting on intrinsic induction (Bi). 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 coercivity and remanent induction. This tool is vital for analyzing magnetic material characteristics.
Demagnetization force refers to the external 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 remanent induction has been reduced to zero. This state is achieved through applying alternating magnetic fields. Demagnetization is important in eliminating unwanted magnetic effects.
The density of a neodymium magnet, typically around 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).
Consider 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).
Consider 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 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 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 poles located on opposite sides of the diameter. They are particularly useful 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 essential for system design.
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 changing magnetic fields. They cause energy losses, heating, or resistive effects. The use of optimized designs minimizes their negative effects.
An electromagnet is a magnet that relies on an electric coil to produce a magnetic field. The strength of the magnetic field depends on the current. Electromagnets are applied in industries and technologies.
The energy product is a measure of the energy stored in a magnetic material. It is calculated as the multiplication of two parameters from the demagnetization curve. Expressed in various units, it is a critical parameter for evaluating the performance and strength of magnets.
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. They combine low electrical conductivity with high magnetic permeability. Used in applications requiring low eddy current losses.
A ferromagnetic material is characterized by its ability to amplify magnetic flux. In such materials, atoms generate a strong magnetic field. Examples include and their alloys. They are widely used due to their permanent magnetic properties.
Flux density, denoted as B, defines the strength of the magnetic field. 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 a critical engineering tool.
Litera: G
Gauss is a unit of magnetic induction. One Gauss (G) equals 10^-4 Tesla (T). Commonly used in laboratory applications.
A Gauss meter is a device for measuring magnetic field strength. It uses Hall effect sensors. Helpful in magnetic diagnostics.
The Gilbert is a unit of magnetomotive force (mmf). One Gilbert represents the field strength needed to produce magnetic flux in a specific circuit.
The grade of a magnet refers to its magnetic properties, such as BHmax or Hc. Higher grades offer better magnetic fields and stability.
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 the magnetic field strength needed to reduce a material's residual induction (Br) to zero. Expressed in SI units, 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 strong and rapidly changing magnetic fields. Applications include and scientific research requiring advanced field parameters.
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 a lack of intensity variations over a given area. 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 changes in magnetic induction (B) as a function of magnetizing force (H). It is used in quality control, energy loss analysis.
The hysteresis loop is a graphical representation of the relationship between magnetic induction (B) and magnetizing force (H). It provides information about the behavior of materials during magnetization cycles.
Hysteresis refers to a material's ability to retain partial magnetization after the external field is removed. 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) describes the strength of the magnetic field in a material or space. 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 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 Alnico magnets or older designs.
Kilogauss (kG) is a unit used to express magnetic induction or flux density. 1 kilogauss = 1000 Gauss. Commonly used in scientific research, magnet testing.
Litera: L
The load line represents a graphical relationship between remanent induction (Bd) and demagnetizing force (Hd). useful for optimizing magnetic applications.
Lodestone is a naturally occurring magnetic material composed of iron oxide (Fe3O4). Historically used for compasses.
Litera: M
A magnet is a material attracting or repelling other magnetic materials. Can be natural, like lodestone, or artificial, such as neodymium.
A magnetic assembly is designed to achieve specific magnetic properties. Used in sensors, magnetic separators.
The magnetic axis is the preferred path of magnetic flux. It connects the poles of the magnet and defines the orientation of its magnetic field.
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. Represented by magnetic flux lines.
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. 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 amount of magnetic flux passing through a unit area.
It is expressed by the formula:
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.
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)
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.
Magnetic flux density is critical for designing devices like motors, generators, or magnetic sensors.
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. Magnetic flux density is a key parameter in designing magnetic systems.
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.
A key parameter in the design of magnetic circuits. Materials with high permeability are more effective at concentrating magnetic fields.
Magnetic poles are regions where the magnetic field is strongest. Pole polarity determines attraction and repulsion forces between magnets.
Beyond saturation, further increases in the external field do not enhance magnetization. This parameter is vital when selecting materials for high-field applications.
Magnetization refers to the result of aligning atomic or molecular magnetic moments in a preferred orientation. It can be achieved by exposure to a magnetic field, electric current flow, or contact with other magnets.
Magnetization is the process of imparting magnetic properties to a material by aligning its magnetic domains. 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 ability to generate a magnetic field in a magnetic circuit. Analogous to electromotive force (EMF) in electrical circuits.
In magnetism, material refers to a substance exhibiting magnetic properties or influenced by a magnetic field. Ferromagnetic materials like iron can be permanently magnetized.
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 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.
It is calculated using the equation:
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. Ensures material stability and performance under specified conditions.
Maxwell is a unit of magnetic flux named after James Clerk Maxwell. 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. 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 a unit used to measure the intensity of the magnetic field (H). mainly used in the CGS system.
An open circuit refers to resulting in a break in the magnetic flux path. 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. Proper orientation is critical to achieving desired magnetic properties and optimizing magnetic systems.
Litera: P
Paramagnetic materials are become magnetized in the direction of the external field due to the alignment of atomic or molecular magnetic moments. 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 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.
Magnetic permeability, 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.
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.
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.
A magnetic pole refers to one of the two ends of a magnet where the magnetic field is strongest: north or south. Their location and properties are critical for optimizing performance in magnetic applications.
Pull force, also known as holding force, describes the force required to separate a magnet from a ferromagnetic surface. It can be estimated 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
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.
Relative permeability is a measure of how easily a material can be magnetized compared to a vacuum. is a crucial parameter in magnetic engineering.
the magnetic equivalent of electrical resistance in current circuits. is a significant parameter in evaluating the effectiveness of magnetic systems.
Reluctance, 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.
This occurs due to opposing magnetic fields generated by the magnets, causing them to repel each other. 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. Is a critical component in designing efficient magnetic circuits.
Litera: S
Shear 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.
It is the pole that, when freely suspended, points toward the Earth's geographic South Pole. Magnetic field lines flow from the north pole to the south pole, defining interaction properties.
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. 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. Anisotropic magnets are used in precise devices like electric motors.
Litera: W
Named after Wilhelm Eduard Weber, a German physicist and pioneer of electromagnetic theory. 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).
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.