Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

This is an AMP page - Open full page! for all features.

Search is the most efficient way to navigate the Engineering ToolBox!

Permeability

Sponsored Links

Permeability is the ability to support formation of magnetic fields in a material.

Permeability is measured in H/m (henries/m) or newtons/ampere2(N/A2) .

The Permeability of Free Space

The permeability of free space µ0 (the permeability constant or the magnetic constant) is

µ0 = 4π 10 -7 (H/m)

≈ 1.257 10-6 (H/m, N/A2)

The Relative Permeability

The relative permeability is the ratio of the permeability of a specific medium to the permeability of free space µ0

µ r = µ / µ0 (1)

where

µ r = relative permeability

µ = permeability of the medium (H/m)

The lowest relative magnetic permeability of a paramagnetic material is 1.0 - and the magnetic response of the material is the same as 'free space' or complete vacuum.

Substances - Permeabilities
MediumPermeability
- µ -
(H/m)
Relative permeability
- μ / μ0 -
Air 1.25663753 10-6 1.00000037
Aluminum 1.256665 10-6 1.000022
Austenitic stainless steel 1) 1.260 10-6 - 8.8 10-6 1.003 – 7
Bismuth 1.25643 10-6 0.999834
Carbon Steel 1.26 10-4 100
Cobalt-Iron (high permeability strip material) 2.3 10-2 18000
Copper 1.256629 10-6 0.999994
Ferrite (nickel zinc) 2.0 10 -5 – 8.0 10-4 16 – 640
Ferritic stainless steel (annealed) 1.26 10-3 - 2.26 10-3 1000 – 1800
Hydrogen 1.2566371 10-6 1
Iron (99.8% pure) 6.3 10-3 5000
Iron (99.95% pure Fe annealed in H) 2.5 10-1 200000
Martensitic stainless steel (annealed) 9.42 10-4 - 1.19 10-3 750 – 950
Martensitic stainless steel (hardened) 5.0 10 -5 - 1.2 10-4 40 – 95
Nanoperm 1.0 10-1 80000
Neodymium magnet 1.32 10-6 1.05
Nickel 1.26 10-4 - 7.54 10-4 100 – 600
Permalloy 1.0 10-2 8000
Platinum 1.256970 10-6 1.000265
Sapphire 1.2566368 10-6 0.99999976
Superconductors 0 0
Teflon 1.2567 10-6 1
Vacuum 0 ) 4π 10 -7 1
Water 1.256627 10-6 0.999992
Wood 1.25663760 10-6 1.00000043

1) Permeability of austenitic stainless steels is not like ferritic, martensitic and duplex stainless steel. Austenitic steel can be classed as paramagnetic with relative permeability approaching 1.0 in the fully austenitic condition. The low permeability enables austenitic steel to be used where a non-magnetic material is required.

Sponsored Links

Related Topics

Electrical

Electrical engineering with units, amps and electrical wiring. Wire gauges, electrical formulas, motors and more.

Material Properties

Properties of gases, fluids and solids. Densities, specific heats, viscosities and more.

Related Documents

Electrical Inductance - Serial and Parallel Connections

Electrical inductance in serial and parallel connected inductors.

Inductance

The Electro Magnetic Field - EMF - induced into a electric circuit.

Inductors - Stored Energy

Energy stored in a magnetic field.

Relative Permittivity - the Dielectric Constant

Common materials and their relative permittivity.

Sponsored Links

Search Engineering ToolBox

Search is the most efficient way to navigate the Engineering ToolBox!

SketchUp Extension - Online 3D modeling!

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro . Add the Engineering ToolBox extension to your SketchUp from the Sketchup Extension Warehouse!

Privacy

We don't collect information from our users. Only emails and answers are saved in our archive. Cookies are only used in the browser to improve user experience.

Some of our calculators and applications let you save application data to your local computer. These applications will - due to browser restrictions - send data between your browser and our server. We don't save this data.

Google use cookies for serving our ads and handling visitor statistics on the AMP pages. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected.

AddThis use cookies for handling links to social media. Please read AddThis Privacy for more information.