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.