The evolution of the distribution of nano-defects that were formed under the effect of tensile stresses existing at the surface of polished foils of Mo was studied. The nano-defects formed 4 statistical ensembles in which the size distribution was determined by the maximum of the configurational entropy. The energy of formation and the average size of nano-defects in adjacent ensembles differed by a factor of 3. When the concentration of nano-defects in one of the ensembles reached a thermodynamically optimum value of about 5%, some of the nano-defects annihilated and the other part became transformed into nano-defects of the next (higher) hierarchical level. The application of a load to the sample studied continuously generates nano-defects that formed the first (lowest-level) ensemble, which led to periodic oscillations in the concentrations of nano-defects in all 4 ensembles.

Hierarchy of Statistical Ensembles of Nanodefects on the Surface of Stressed Molybdenum. A.Y.Bashkarev, V.I.Vettegren, V.N.Svetlov: Physics of the Solid State, 2002, 44[7], 1316-22