Optoacoustic Effects in Pentaerythritol Tetranitrate with Ultrafine Aluminum-Particle Inclusions under Pulsed-Laser Action

Abstract–Results of studying optoacoustic characteristics of pentaerythritol tetranitrate (PETN) specimens with inclusions of ultrafine aluminum particles (100 nm) are presented. Regularities of the increase of extinction coefficient £_ef and signal amplitude Uon a piezodetector by increasing laser-pulse fluence Я have been established. Estimates have been made, and it has been concluded that, during a laser pulse, heating of alu­minum inclusions and a shell surrounding it occurs up to a gasification temperature and appear craters on a specimen's surface appear at H > 0.1 J/cm².