{"id":7657,"date":"2025-05-15T01:30:08","date_gmt":"2025-05-15T01:30:08","guid":{"rendered":"https:\/\/osencmag.com\/?p=7657"},"modified":"2025-05-27T05:26:43","modified_gmt":"2025-05-27T05:26:43","slug":"magnetic-permeability-explained-formula-types-material-table","status":"publish","type":"post","link":"https:\/\/osencmag.com\/fr\/blog\/magnetic-permeability-explained\/","title":{"rendered":"La perm\u00e9abilit\u00e9 magn\u00e9tique expliqu\u00e9e : Formule, types et tableau des mat\u00e9riaux"},"content":{"rendered":"\t\t
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Magnetic permeability\u2014the cornerstone of electromagnetic material science\u2014defines how substances respond to magnetic fields. From Maxwell\u2019s equations to modern power systems, this fundamental property shapes technological progress. At Osencmag, we combine rigorous research with industrial expertise to advance permeability measurement and material innovation.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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What is magnetic permeability?<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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Magnetic permeability\u2014a material\u2019s ability to develop an internal magnetic field under an external influence\u2014is a cornerstone of magnetics. Coined by Oliver Heaviside in 1885, it quantifies how readily a material responds to an applied field, shaping the resulting magnetic interactions.<\/span><\/p>

When a ferrous material is drawn to a magnet, permeability dictates the strength of the induced magnetization. The higher the permeability, the more intense the material\u2019s internal field and the stronger the attraction.<\/span><\/p>

Yet permeability is not static. It varies with temperature, processing history, field strength, and environmental factors\u2014making it a dynamic property rather than a fixed value. This complexity is what makes it so compelling: permeability reveals how materials adapt to magnetic fields, offering insights into their fundamental behavior.<\/span><\/p>

To study it is to explore the nuanced relationship between matter and magnetism\u2014a field where theory and real-world response intertwine.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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How to calculate magnetic permeability?\n<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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Magnetic permeability \u03bc (Greek mu) is defined as: \u03bc=B\/H
<\/strong><\/span>where B is the magnetic flux density and H is the magnetic field strength.<\/span><\/p>

In these systems, the permeability B\/H is called the absolute permeability \u03bc of the medium. The relative permeability \u03bc\u1d63 is then defined as the ratio \u03bc \/ \u03bc\u2080, which is dimensionless. This relationship lies at the heart of how we<\/a> quantify the magnetic response of materials and is a foundational equation in electromagnetism.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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What is the vacuum magnetic permeability in natural unit?<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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In metre\u2013kilogram\u2013second (mks) and SI units, the permeability of free space (symbolized \u03bc\u2080) was defined as equal to 4\u03c0 \u00d7 10\u207b\u2077 weber per ampere-metre. However, with the redefinition of the ampere in 2019, \u03bc\u2080 is no longer exactly equal to 4\u03c0 \u00d7 10\u207b\u2077, and must be determined experimentally. That said, the deviation is extremely small: [\u03bc\u2080 \/ (4\u03c0 \u00d7 10\u207b\u2077)] \u2248 1.00000000055, still very close to its former value.
This constancy of the vacuum\u2019s magnetic response reminds me that even the seeming void of space holds a quiet but measurable structure\u2014a beautiful interplay of fundamental constants.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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What is magnetic permeability of free space?<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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The permeability of free space, also known as the permeability of air or vacuum \u03bc\u2080, is one of those constants that gets tossed around frequently in electromagnetism, and yet, it\u2019s quite the unsung hero of the physics world. Think of it as the measure of how much “magnetic freedom” space (vacuum or air) offers to the magnetic field.
Mathematically, \u03bc\u2080 is the ratio of magnetic flux density B0\u200b to the magnetic field intensity H in a vacuum:<\/span><\/p>

\"Formula<\/p>

This is not just any number\u2014it\u2019s a physical constant that we can count on. In fact, its exact value is:<\/span><\/p>

\"Physical<\/p>

or equivalently<\/span><\/p>

\"Physical<\/p>

or in another context, \u03bc\u2080\u200b is<\/span><\/p>

\"Physical<\/p>

\u00a0<\/span> (henrys per metre)<\/span><\/p>

Now, here\u2019s the twist: \u03bc\u2080 is tied to the speed of light in the most elegant way possible. There\u2019s a beautiful equation that connects \u03bc\u2080 to the speed of light c and the permittivity of free space \u03b50\u200b:<\/span><\/p>

\"Formula<\/p>

It\u2019s like the perfect trio in physics\u2014c,\u03bc\u2080, and \u03b50\u200b\u2014dancing together in harmony.<\/span><\/p>

Now, what does this constant really do for us, practically speaking? Well, it\u2019s used to calculate magnetic force between two electric currents. The constant \u03bc\u2080 gives us a measure of how strong the magnetic force is between two wires carrying currents. Here\u2019s the magic formula:<\/span><\/p>

\"Formula<\/p>

Where:<\/span><\/p>