Shielding Materials Kamp;J Magnetics
The higher the number, the better the shield. Low carbon steels have a Permeability of 1000 3000, while MuMetal can have values as high as 300,000 400,000. The saturation point is the flux density at which the material can not contain any more magnetic flux. Steel saturates around 22,000 Gauss, while MuMetal saturates at about 8,000 Gauss.