Remanent magnetization of instrument materials for low magnetic field applications

We report remanent magnetization and magnetic susceptibility measurements made on materials used in the construction of cryogenic instruments. SQUID based magnetometers were used to make the measurements over a range of background fields from 102 to 10−7 Gauss. Although the materials tested are generally regarded as nonmagnetic, some samples have sufficiently high magnetization values, or values which vary with foundry lot and heat, that use in low field or magnetically sensitive applications is contraindicated.