Magnetoelastic Vibration Dampers

Magnetoelastic dampers have been proposed for use in suppressing vibrations of large motors and transformers that operate at temperatures below 100 K. [Also see "Progress in Magnetoelastic Vibration Dampers," (NPO-20887) on page 57 of this issue.] These dampers would be made of magnetostrictive materials - specifically, Tb/Dy alloys. It would not be necessary to use the rare and expensive high-purity grades of Tb/ Dy; the commercial grade would suffice and may in fact be preferable.