You Decide
Magnetostrictive Materials were discovered in the 1840s by James
Prescott Joule, when he noticed that iron changed length in response
to changes in magnetism and named the phenomenon the Joule Effect.
How It Works:
Magnetostrictive
materials expand when exposed to a magnetic field, exhibiting
the Joule Effect or Magnetostriction.
This occurs because magnetic domains in the material align with the
magnetic field. Similarly,
when the material is strained
(stretched or compressed), its magnetic energy changes. This
phenomenon is called magnetomechanical
effect or Villari Effect.
Magnetostrictive materials can operate at higher temperatures than piezoelectric and electrostricive actuators. They can also undergo higher strains and lower input voltages that most piezoelectric and electrostrictive materials can. However, magnetostrictive materials are not easily embedded in control structures.
Some kinds of magnetostrictive materials:
- cobalt
- iron
- nickel
- ferrite
- terbium Alloys (Terfenol-D)
- metglass
Examples of Applications and Links:
When you click on these sites,
you may be exiting the NASA web site. These sites are not under NASA
control, and NASA is not
responsible for the information or links you may find there. NASA is
providing these links
only as a convenience. The
presence of these links on any NASA web site is not intended to imply
NASA endorsement of that
site, but to provide a
convenient link to relevant sites which are managed by other
organizations, companies, or individuals.
- Active sensing and actuation in automobiles, which is explained complete with graphics at: http://www.sensorland.com/HowPage024.html
- Sonar in Collision Avoidance in Automobiles: http://www.physics.hull.ac.uk/magnetics/Research/Facilities/Magnetostriction/Applications/applications.html
- Active Cabin Noise Control in Automobiles
- Dampening for surgical tools
You Decide Intro
You Decide Scenario
You Decide Decision Making Process