Numerous investigations demonstrated experimentally the possibility of ion irradiation to affect the structure and properties of solids in the layers that are as far from the surface as several micrometer or more ('long-range effect,' LRE). The special kind of LRE is the throughout penetrating alteration of mechanical properties of metal foils (10 - 100 micrometer thick) under low doses (1013 - 1016 cm-2) of ion irradiation ('low-dose long-range effect,' LDLRE). At such doses and ion fluxes used (j less than 10 (mu) A/cm2), substrate heating is small. Therefore, the mechanisms involving macroscopic temperature rise may be excluded (deep diffusion of impurities, plastic strain due to temperature gradients, etc.). As some investigations show, similarly phenomena take place not only for ion irradiation but for many other actions on surface layers of solids: friction, lapping, polishing, chemical and chemical-mechanical etching, plasma-etching, etc. Recently, we established that even such a 'soft' irradiation as one with 0.95 micrometer light causes the increase of microhardness on the back side of 20 micrometer-thick permolloy-79 foil. This phenomenon presents actually the long-range effect for light irradiation; it was named by us 'the effect of mechanical photo-memory of metals' (EMPMM). In this report, we briefly review the regularities of LDLRE and EMPMM. Further, we discuss models of these effects and give some arguments in favor of suggested model of EMPMM basing on our results of molecular-dynamical computation.
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