Doklady Earth Sciences 05/2012; 413(1):155-159. · 0.38 Impact Factor
ABSTRACT: The applicability of a tribospectral analysis to the detection of nanoscale inhomogeneities and discontinuities at the nanocoating-substrate
interface has been substantiated theoretically. The approach put forward in this work is based on the measurement of the counterbody
sliding resistance force coupled with an analysis of its frequency spectrum. A theoretical study on the potentialities and
limitations of nanotribospectroscopy has been performed with the use of a computer simulation by the method of movable cellular
automata. The results of the investigation have shown, among other things, the possibility to estimate a number of parameters
of nanoscale discontinuities (characteristic spacing, linear size, etc.). To obtain reliable information on the defect structure
and spacing, nanotribospectroscopy must be supplemented by other diagnostic methods. The design of a prototype nanotribospectrometer
with spatial resolution up to 8 nm is described. Applications of the examined approach as a promising nondestructive-testing
technique for assessment of nanostructured coating and surface layer damage are discussed.
Russian Physics Journal 04/2012; 52(4):380-385. · 0.41 Impact Factor
ABSTRACT: The paper concerns the development of a formalism of the movable cellular automata method for simulation of consolidated heterogeneous elastoplastic media at different scale levels. Using the developed formalism as the basis, an approach was formulated for construction of structural models that describe mesoscopic response (including fracture) of heterogeneous media to loading with regard to hierarchical organization of their internal structure. In the approach, the effect of structural scale levels higher than the level under consideration is taken into account by a technique combining the particle method and conventional methods of continuum mechanics. The effect of lower structural scale levels is taken into account by determining integral response characteristics of lower-scale representative volumes and by specifying appropriate values of particle interaction parameters. The proposed formalism was advanced for description of contrast heterogeneous media whose components can assume different aggregate states. The potentialities of the particle method for description of hierarchically organized media are illustrated by studying the response and fracture mechanisms of materials, including contrast media, with a developed porous structure.
Physical Mesomechanics 01/2011; 14(5-6):224. · 1.55 Impact Factor
ABSTRACT: We have studied the possibility of producing a directed action upon the process of local stress relaxation in interfacial
media occurring in a complex stressed state by changing the state of boundaries between structural elements. The experiments
were performed on the ice sheet of Lake Baikal, which represents a hierarchically organized fault-block structure and belongs
to the class of interfacial media. It is shown that, by changing the state of boundaries between structural elements, it is
possible to influence the regime of deformation of the interfacial medium as a whole. The general features of the observed
effect are confirmed within the framework of a theoretical model.
Technical Physics Letters 07/2005; 31(8):712-715. · 0.56 Impact Factor
ABSTRACT: The field investigations carried out recently have shown that an effective model medium for studying geotectonic processes can be the ice cover of Lake Baikal, which is a classical example of hierarchically organized block-structured media. Many significant deformation mechanisms of the block-structured ice cover can be compared to the mechanisms known in geodynamics, such as spreading, subduction, pull-apart and other ones. The present paper contains the results of studying dynamic processes of formation and evolution of one of the mentioned deformation-induced structures in the Baikal ice cover, namely, an underride zone that can be considered as a subduction zone analog. It is shown that these processes can be induced by dynamic relaxation events related either to the formation of new interfaces (fragmentation of blocks) or to the activation of the existing but earlier inactive cracks. A supposition is made that fragmentation accompanied by releasing a large amount of elastic energy can be one of possible mechanisms of forming compression impulse, which is considered to be necessary for initiation of subduction in the lithosphere. The processes of forming underride and subduction zones are compared and their qualitative similarity is revealed. After examining the structure of contact between ice plates in the underride zone the conclusion was made that formation of the deformation-induced structure under consideration allows reducing the compression resistance of the plate boundary by orders of magnitude. This suggests that structures of subduction type make for an effective mechanism of realization of high inelastic deformations in block-structured media without noticeable stress growth.