Cryogenic Magnetic Shielding

Often times, we receive requests to fabricate magnetic shields to be used at cryogenic temperatures (4.2k). Standard high permeability materials mumetal and HyMu 80 (specs ASTM A753 Alloy Type 4, and MIL-N-14411 Composition 1) are meant to be used at room temperature, so their maximum permeability will degrade and the magnetic shields will saturate as the application reaches cryogenic temperatures. Fortunately, a material called Cryoperm was developed to withstand the extreme cold or cryogenic temperatures.