Wideband sonar energy absorber

摘要

This invention relates to an acoustic energy absorbing material which absorbs sound energy underwater and its performance is independent of the surrounding hydrostatic pressure. It consists of a non-conducting elastomeric matrix having piezoelectric or magnetostrictive particles disposed therein for converting incident soundwave energy into heat, a corrosion resistant coating on the particles for optimizing energy absorption of sonar waves of predetermined frequency, the elastomeric matrix designed so as to have a Poisson's ratio of about 0.5 for effectively utilizing all particles so the incident soundwaves are applied to the particles as a hydrostatic stress distribution, and the acoustic energy absorbing material consisting of a plurality of thin layers of the elastomeric matrix and having high energy absorption per unit volume for providing a slight impedance mismatch between successive layers thus absorbing the predetermined energy of the soundwaves.