THEORETICAL APPROACH TO THE DEFORMATION-INDUCED LUMINESCENCE IN METALS

The present paper reports the mechanoluminescence (ML) produced during fracture of metals. The mechanism of ML in metals is based on the gen eration of holes during the decay of mobile dislocations on the surfac e and subsequent electron-hole radiative recombination. The following equation is derived for the transient ML intensity of the fracto-induc ed ML in metals I = eta g(0)[exp (-alpha t) - exp (-beta t)], where g( 0) = PhNd delta(p)/at(c) = P-h epsilon/ab. The above equation shows th at I should be maximum for a particular value of time t. For beta much greater than a, I = eta g(0)[exp (alpha t)]. This equation shows that I should decrease exponentially with time. For the fracto-induced ML in metals, t(m) and I-m may be expressed by the following equations t( m) = 1/beta ln (beta/alpha) and I-m = eta PhNd delta(p)/at(c). The spe ctroscopy of ML in metals is also discussed. A good correlation is fou nd between the theoretical and experimentals results.