Highly Magnetostrictive Rare Earth-Iron Alloys.
Abstract
Since 1963, it has been known that the rare earth elements possess extraordinary magnetostrictions (approx. .06), far in excess of those characteristic of the magnetic transition metals and alloys. These magnetostrains, however, are available only at cryogenic temperatures. Within the last few years, magnetostrictive strains exceeding .002500 have been achieved at room temperature in rare earth alloys containing Tb and Fe. These alloys possess the largest known room temperature magnetostrictions by far and maintain the largest known magnetomechanical coupling factor (k = 0.6) over wide ranges in applied field. Recently, both positive and negative magnetostrictive materials have been examined. In this technical report, an introduction to the highly magnetostrictive rare earths is given. Measurements on polycrystals and single crystals are presented. The importance of grain orientation in the fabrication of transducer elements is established. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1976
- Accession Number
- ADA038251
Entities
People
- A. E. Clark
Organizations
- Naval Ordnance Laboratory