Magnetostrictive rare earth materials

When the external magnetic field changes, the length and the size of magnetic material will be a minor change, this phenomenon is known as the magnetostriction. Changes in the length of which called linear magnetostriction, the changes in volume as the volume magnetostriction. Volume magnetostriction is much weaker than linear magnetostriction,so the magnetostriction we general mentioned is linear magnetostriction.

Since the magnetic materials with different magnetic state will have different flexibility, so they will have a mechanical vibration if putting on a alternating magnetic field. In this way, the transformation of electromagnetic energy into mechanical energy is achieved.
To use of such magnetostrictive characteristics, we can create variety of energy transformation devices which transform electromagnetic energy into mechanical energy and vice versa. For example: Sonar: the general frequency sonar launched in more than 2 kHz, but low-frequency sonar which frequency is low than 2KHz have special advantages: the lower the frequency, the lower decay is and the longer distance the sound wave transmits, also the smaller impact of shield of no echo under water, the sonar system made of Terfenol-D materials can meet the high-power, small size, low-
frequency requirements.

Transducer: mainly used for small movements controlled device - actuators. Including servo pump, fuel injection system, brakes and so on. They are used in automobiles, aircraft, spacecraft, robotics, precision machine tools, precision instruments, computers, optical communications, printing. Sensors and electronic devices: such pocket-sized asmagnetic measurementd device, detect displacement, force and acceleration sensors and the tuneable surface acoustic wave devices and so
on. the electronic devices are used for radar, the phase sensor of sonar and the computer storage devices.
Neodymium (more precisely Neodymium-Iron-Boron) magnets are the strongest permanent magnets in the world.

Tags: neodymium magnets Magnetostrictive rare earth materials Smco magnets