Photon emission from metals under fast nondestructive loading

A study is reported of the mechanoluminescence excited on the backside of m etal samples whose front side is irradiated by single laser pulses with an energy below the onset of spallation. The temporal and spatial distribution s of temperature, thermal stresses, and thermal-stress variation rates are calculated. The temporal dependence of mechanoluminescence from metal targe ts is compared with calculations of the mechanical stresses initiated in th e targets under pulsed loading. The dynamics of the emission process are sh own to be governed by those of loading. (C) 2000 American Institute of Phys ics. [S0021-8979(00)02005-3].