Magnetic Shielding Frequently Asked Questions

Magnetic Shielding FAQs

What causes a magnetic field?

Most magnetic fields are man made. They can be found in solenoids, bar magnets, and some motors and transformers. Magnetic fields are used in creative ways to create sound (speakers), microscopic images (microscopy), and record resonance images through MRI technology. In some cases, however, the fields interfere with sensitive electronic equipment, and shielding is necessary.

How does magnetic shielding work?

When magnetic lines of flux encounter high permeability material, the magnetic forces are both absorbed by the material and redirected away from its target, much as a beavers dam absorbs and reroutes water from its den.

The most effective shields are constructed as enclosures such as boxes or better yet, cylinders with end caps. Because the field follows the line of the enclosure, an enclosed shape keeps stray fields from finding gaps which could cause unintended interference.

What is "permeability"?

Imagine a sponge. Some sponges have big holes, some are more tightly structured, each absorbs liquid to a point of saturation. Magnetic shielding material is similar. Depending upon its structure, magnetic shielding material absorbs magnetic interference to a point of saturation. As magnetic interference increases, so too should the permeability of the material.

What is Mumetal®?

Pronounced "mew metal", Mumetal® is a trade name for one of several high permeability magnetic shielding materials. It is made up of about 80% nickel. Often times Mumetal® is used as a generic word to designate a high permeability alloy. Depending upon the mix, the remainder of the materials include iron, molybdenum or chromium, and copper. Other trade names include Permalloy®, HyMu-80®, Hipernom®, Magnifer 7904®, Magnifer 75®, and Mumetal 2®. MuShield works with all of these products and will help you to determine which is the most appropriate material for your application.

Why should I purchase my magnetic shielding from MµShield?

We are selected by our customers to be their magnetic shielding vendor because they count on us for a consistent product at a reasonable price.

Our goal is "shielding that works" our end result is a satisfied customer.

Additional FAQ reading?

This is a partial list of the most commonly asked questions regarding MuShield, MuMetal® and applications of magnetic shielding materials. For a more complete list, please visit MuShield.com FAQ page.