Examination of the Shape Variation and Stress Distribution of Vibration Elements Using Giant Magnetostrictive Material

Acoustic vibration elements using giant magnetostrictive material (AVEG) are employed as vibration sources for under-sea acoustic propagation over distances of 1000 km or more. In this paper the magnetic circuit of the driving unit was analyzed using the finite element method. The flux density distribution is nonuniform in the magnetostrictive vibrator. Converting flux density B into magnetostriction ¿, we examine the difference in the shape variation and stress distribution of the magnetostrictive vibrator. We also show the influence on magnetic coupling of magnetostrictive vibrators that are constructed with eight pieces of the AVEG arranged octagonally.