Mumetal is to eliminate magnetic lines of flux? I am trying to isolate a magnet in a protective housing.
I know there are different types of this, like 70%, 90% and one that is 99%. I like the flexibility of the 70% if it accomplishes what I require. My thought is that if you use 2 layers that would in effect cancel all interference that could be caused.
Any thoughts or comments would be greatly appreciate.
Jim
The high permeability of mu-metal provides a low reluctance path for magnetic flux, leading to its major use, in magnetic shields against static or slowly varying magnetic fields. Magnetic shielding made with high permeability alloys like mu-metal works not by blocking magnetic fields but by providing a path for the magnetic field lines around the shielded area. So the best shape for shields is a closed container surrounding the shielded space. The effectiveness of mu-metal shielding decreases with the alloy's permeability, which drops off at both low field strengths and, due to saturation, at high field strengths. So mu-metal shields are often made of several enclosures one inside the other, each of which successively reduces the field inside it. Because mu-metal saturates at such low fields, sometimes the outer layer in such multilayer shields is made of ordinary steel. Its higher saturation value allows it to handle stronger magnetic fields, reducing them to a lower level which can be shielded effectively by the inner mu-metal layers.
http://en.wikipedia.org/wiki/Mu-metal
After doing more reading this will work, just didn't expect to be doing more then two layers.
I know there are different types of this, like 70%, 90% and one that is 99%. I like the flexibility of the 70% if it accomplishes what I require. My thought is that if you use 2 layers that would in effect cancel all interference that could be caused.
Any thoughts or comments would be greatly appreciate.
Jim
The high permeability of mu-metal provides a low reluctance path for magnetic flux, leading to its major use, in magnetic shields against static or slowly varying magnetic fields. Magnetic shielding made with high permeability alloys like mu-metal works not by blocking magnetic fields but by providing a path for the magnetic field lines around the shielded area. So the best shape for shields is a closed container surrounding the shielded space. The effectiveness of mu-metal shielding decreases with the alloy's permeability, which drops off at both low field strengths and, due to saturation, at high field strengths. So mu-metal shields are often made of several enclosures one inside the other, each of which successively reduces the field inside it. Because mu-metal saturates at such low fields, sometimes the outer layer in such multilayer shields is made of ordinary steel. Its higher saturation value allows it to handle stronger magnetic fields, reducing them to a lower level which can be shielded effectively by the inner mu-metal layers.
http://en.wikipedia.org/wiki/Mu-metal
After doing more reading this will work, just didn't expect to be doing more then two layers.
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