Magnet parameters determine characteristics and behavior.
This post lists fundamental parameters that define strong magnets.
Learn about flux, coercivity, energy density, and more.
Discover how parameters influence performance and applications.
If you need a magnet parameter overview, read on.
Let’s dive into this essential magnetics reference list.
Residual Induction (Br)
Residual induction refers to the magnetism retained by a neodymium magnet after being magnetized to saturation and removed from the magnetizing field.
It indicates how strongly the magnet will exert attractive and repulsive forces on other materials once magnetized.
The higher the residual induction, the stronger the magnetic field produced.
Magnetic Flux Density (B)
Magnetic flux density, also known as magnetic induction, is a measure of the magnetic field produced by a magnet. It’s super important because it helps us figure out how strong a magnet is.
Definition and Unit
Magnetic flux density is represented by the symbol “B” and is measured in a unit called the Tesla (T). One Tesla is equal to one Weber per square meter. But don’t stress too much about the units – just remember that a higher value of B means a stronger magnetic field.
Applications
Magnetic flux density is crucial in many applications, such as in electric motors and generators, where strong magnetic fields are needed for efficient operation.
Magnetization (M)
Magnetization is all about the alignment of the tiny magnetic domains within a magnet. The more aligned they are, the stronger the magnet will be.
Definition and Unit
Magnetization, represented by the symbol “M,” is measured in Amperes per meter (A/m). It tells us the degree to which a material can be magnetized. A higher value of M means better magnetization and a stronger magnet.
Applications
Magnetization is important in applications like data storage devices (think hard drives) and magnetic sensors, where the strength and stability of the magnetic field are crucial.
Coercivity (Hcj)
Coercivity measures how resistant the magnet is to becoming demagnetized. It is the strength of the external magnetic field required to reduce the magnetization of a neodymium magnet to zero after being saturated. Stronger coercivity means it is more difficult for opposing magnetic fields to weaken the magnet.
Coercivity is all about a magnet’s resistance to demagnetization.
In other words, it tells us how hard it is to weaken or destroy a magnet’s magnetic field.
Definition and Unit
Coercivity, represented by the symbol “Hc,” is measured in Oersteds (Oe) or A/m. A higher value of Hc means a magnet is more resistant to demagnetization, which is definitely a good thing!
Applications
Coercivity is a key parameter in applications where magnets need to maintain their magnetic properties under extreme conditions, such as high temperatures or exposure to other magnetic fields.
Maximum Energy Product (BHmax)
The maximum energy product is a measure of the maximum amount of magnetic energy that can be stored in a magnet.
It’s a super useful parameter because it helps us find the most efficient magnet for a particular application.
The maximum energy product represents the maximum density of magnetic energy that can be generated in the air gap between the magnet’s poles. It correlates to the strength of the magnetic field in that gap. Larger values indicate the magnet can produce very strong field strengths in the gap between its north and south poles.
Definition and Unit
The maximum energy product is represented by the symbol “BHmax” and is measured in Mega-Gauss-Oersteds (MGOe) or kilojoules per cubic meter (kJ/m³). A higher value of BHmax means a magnet can store more energy, making it more efficient.
Applications
The maximum energy product is particularly important in applications where space is limited, such as in miniaturized electronic devices or motors. In these cases, we want magnets with high BHmax values to achieve the best performance in the smallest possible size.
Intrinsic Coercivity (Hci)
Intrinsic coercivity specifically measures the demagnetization resistance of the NdFeB material itself, independent of the magnet’s shape.
It is the reverse external field required to drive the material’s residual magnetization to zero after being saturated.
Higher intrinsic coercivity materials can better withstand demagnetizing factors.
Conclusion
This post covered the key parameters that determine magnet performance.
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