MUMETAL® magnetic shielding prevents magnetic fields from reaching areas where they would cause magnetic interference. Magnetic shielding is used around either the source of interference, to prevent electromagnetic radiation from leaving a device; or more typically, around a sensitive device, to prevent the electro magnetic interference (EMI) from disrupting normal operations.

EMI can be a problem to designers of many products. Personal Computer manufacturers must design to meet the FCC Part 15 regulations to prevent PCs from interfering with other office equipment. Cell phone designers have to incorporate RFI shielding to stop unwanted RF emissions, as well as to prevent other electrical equipment from interfering with the cellular telephone's operation. Designers may find that densely packed electronic assemblies may have internal components that interfere with each other, requiring electromagnetic shielding. When the electromagnetic interference includes low frequency radiation, magnetic shielding is essential to assure proper operation of the electronic equipment.

There is no known material that blocks magnetic fields without itself being attracted to the magnetic force. Magnetic fields can only be redirected, not created or removed. To do this, high-permeability shielding alloys like MUMETAL are used. The magnetic field lines are strongly attracted into the shielding material.

MUMETAL magnetic shielding material is available on this site in 30 inch by 120 inch sheet form, in seven thicknesses. Sheets can be sheared from 120 inch sheets into shorter lengths for ease of shipping. MUMETAL is made in the U.S.A. and stocked in our distribution facility near O'Hare airport in Chicago.

Founded in 1941, we are the oldest company devoted exclusively to solving problems of magnetic interference and have been involved with thousands of applications. Our quality and processes are world-class. We are ISO 9001:2000 Certified. We want to be your Preferred Source for MUMETAL and answers dealing with your problems of Electro Magnetic Interference (EMI).

Material	MUMETAL®
Specifications	ASTM A-753, Alloy 4; MIL N-14411C Composition 1
Characteristics	An alloy with exceptionally high magnetic permeability, very low coercive force, very low core losses, and low remnance by magnetic field annealing. The alloy finds application in magnetic shielding where fields much less than the Earth's magnetic field are required. Final annealing is necessary to develop magnetic shielding performance.
Typical Annealed Properties
0.2% Yield Strength	49 ksi (338 MPa)
Density	0.316 lb/in3 (8.25 g/cm3)
Tensile Strength	99 ksi (682 MPa)
Electrical Resistivity	47 microhm cm
Elongation	32% in 2" (51 mm)
Grain Size	ASTM 7 or finer (Mill annealed)
Hardness	15T 85
Availabilities
Sheet Form	Width: 30" (762 mm) Thickness: 0.014", 0.020", 0.025", 0.030", 0.040", 0.050", 0.062" (0,36mm; 0,51mm; 0,64mm; 0,76mm, 1,02mm; 1,27mm, 1,57mm) Length: 120" (3048mm)

Typical Chemistry (Wt.%) C 0.015 Mn 0.50 P 0.005 max S 0.001 max Si 0.30 Cr 0.02 max Ni 80.20 Mo 4.85 Al 0.01 max Co 0.02 max Fe Balance

Special Properties Magnetic Properties* DC μ @ 40 gauss 80,000 DC μ @ 100 gauss 105,000 DC μ maximum 350,000 DC Hc 0.005 Oe DC Br (gauss) 4000 AC 60Hz μ @ 40 gauss 65,000 *0.014" (0.36 mm) test sample thickness after test lab anneal.

Data are typical and should not be construed as maximum or minimum values for specification or for final design. Data on any particular piece of material may vary from those shown herein.

Magnetic Shield Corporation
740 N. Thomas
Bensenville, IL 60106

Phone: 877-290-5558
Fax: 630-766-2813
info@mumetals.com

©1997-2005 Magnetic Shield Corp. MUMETAL® is a registered trademark of Magnetic Shield Corporation.