Glossary of magnetic terminology
How to navigate the world of neodymium magnets?
Hello to our comprehensive glossary focused on the fascinating world of neodymium magnets. As a leading expert in providing top-notch magnetic solutions, we understand how crucial it is to have a solid knowledge about the concepts in this unique field. This glossary has been meticulously prepared to serve as an invaluable source of information for anyone who is curious about magnets – whether or not you are an experienced industry professional, a hobbyist, or someone simply curious the applications of magnets.
In our glossary, you will find clear and detailed explanations of key terms and subjects related to neodymium magnets. From the basics of field mechanics and flux density, to material characteristics and magnetic innovations, each definition has been crafted to expand your understanding and ease the comprehension of even the sophisticated ideas. Regardless of whether you are studying industrial applications, carrying out research projects, or simply delving into magnetism, this glossary aims to support your learning.
Discover the fascinating world of neodymium magnets with ease. Broaden your understanding, uncover new insights, and unlock the potential of these exceptional materials, understanding terms and concepts that describe their operation and utility. Use this glossary your guide in delving into the ever-evolving world 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 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. Anisotropic magnets 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 the material to be tailored to application requirements.
Axial magnetization means that the magnetic poles are located at opposite ends of the magnet, and the lines of force 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 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 magnetizing force (H). 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 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 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. Despite being succeeded by the MKSA (SI) system, C.G.S. is still relevant in historical and specialized analyses. 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 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.
Coercivity measures a magnetic material's resistance to demagnetization. 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 exhibit long-lasting magnetic characteristics.
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 reducing or eliminating magnetization. Methods include or employing demagnetization techniques such as degaussing. This process is essential in applications requiring precise control of magnetization.
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 vital for analyzing magnetic material characteristics.
Demagnetization force refers to the opposing magnetic field that induces demagnetization. This force allows for manipulating magnetic properties.
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).
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 produce a repelling effect. 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 creating a circular magnetic field pattern. They are particularly useful in applications requiring radial or rotational interactions.
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. 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 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 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. Adjusting the current allows control over the magnetic field. Electromagnets are widely used 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 an essential measure 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 substances primarily composed of iron oxide (Fe2O3). Renowned for their high-frequency properties. Used in transformers, inductors, and telecommunication devices.
A ferromagnetic material is characterized by strong magnetic properties. In such materials, atoms generate a strong magnetic field. Examples include and their alloys. These materials are fundamental due to their permanent magnetic properties.
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 designing magnetic systems.
A fluxmeter is used to quantify the magnetic field strength. It employs various technologies such as to provide precise measurements. 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). Commonly used in laboratory applications.
A Gauss meter is a device for measuring magnetic field strength. or other techniques to read values in Gauss (G) or Tesla (T). Helpful in magnetic diagnostics.
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. Hall sensors are widely utilized in electronics, such as ABS systems in vehicles.
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 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 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 crucial for applications requiring precise magnetic fields.
A horseshoe magnet has its poles placed close together. 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 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 a transformation of energy into heat. 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 critical for component fitment.
Magnetic induction (B) represents the amount of magnetic flux passing through a unit area. It is measured in standard SI units. Essential for designing and analyzing magnetic systems.
Irreversible losses refer to the effects of high temperatures, mechanical stress, or demagnetizing fields. 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 historical magnet models.
Kilogauss (kG) is a unit of magnetic field measurement. 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 the first known natural magnet. 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 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. key to designing magnetic devices.
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. Represented by magnetic flux lines.
Magnetic field strength (H) is a measure of the magnetizing force applied to a magnetic material. Depends on the current flowing through the conductor.
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 number of magnetic field lines intersecting a surface.
The equation for it is:
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.
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)
If the area is 0.05 m² and the magnetic flux is 0.002 Weber, the resulting flux density is 0.04 Tesla.
A high B value indicates a stronger magnetic field, essential in industrial and medical applications.
The hysteresis loop illustrates the behavior of magnetic materials during cycles of magnetization and demagnetization. Ideal for applications in transformers and electric motors.
expressed in units like teslas (T) in the SI system or gausses (G) in the CGS system. 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 the route taken by magnetic flux in a magnetic circuit or system. A well-designed path ensures efficient magnetic energy transmission.
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. 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 result of aligning atomic or molecular magnetic moments in a preferred orientation. 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 a graphical depiction of a material's magnetic properties. 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. Expressed in ampere-turns (At) or gilberts (Gb).
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, 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 a unit of magnetic flux named after James Clerk Maxwell. 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 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. 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. 1 oersted corresponds to the field that exerts a force of one dyne on a unit magnetic pole at a distance of one centimeter.
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. examples include aluminum, manganese, and oxygen.
Paramagnetism is occurs when materials develop a temporary magnetic moment in the direction of the field. 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. used in electric motors, generators, magnetic storage devices, and speakers.
They are made from materials with high magnetic retention. They are used in devices requiring a constant magnetic field, such as speakers, motors, and generators.
Magnetic permeability is a property of a material determining its ability to conduct magnetic flux. High permeability enables efficient transmission of magnetic flux, critical for designing magnetic circuits.
Permeance, denoted by the symbol P, describes the ease with which magnetic flux can flow through a specific magnetic circuit.
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 instance, a material with a large cross-sectional area and short magnetic path exhibits high permeance, making it efficient in magnetic applications.
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 instance, a material with a large cross-sectional area and short magnetic path exhibits high permeance, making it efficient in magnetic applications.
High permeability is crucial for enhancing the efficiency of magnetic systems.
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.
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 a magnet's ability to maintain attachment. 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: 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. Due to their high magnetic strength, they are used in industries, electronics, and consumer technologies.
Rare earth magnets, such as neodymium, are known for their exceptional magnetic strength. 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.
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)
The larger the magnetic cross-section or permeability, the lower the magnetic resistance.
Understanding reluctance allows optimization of systems such as electromagnets, transformers, and electric motors.
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)
The larger the magnetic cross-section or permeability, the lower the magnetic resistance.
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. Allows for assessing the long-term stability and suitability of magnets for various applications.
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
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.
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.
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
Neodymium magnets can produce high levels of magnetic field strength, measured in teslas (T) or subunits like milliteslas (mT). The unit is named after Nikola Tesla, a renowned inventor and physicist whose work revolutionized electromagnetism.
Isotropic magnets can be magnetized in any direction, making them versatile. Isotropic magnets are ideal for general applications due to their flexibility.
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 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.