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Nanoscience and Technology: An International Journal
ESCI SJR: 0.228 SNIP: 0.484 CiteScore™: 0.37

ISSN Druckformat: 2572-4258
ISSN Online: 2572-4266

Nanoscience and Technology: An International Journal

Formerly Known as Nanomechanics Science and Technology: An International Journal

DOI: 10.1615/NanomechanicsSciTechnolIntJ.v6.i3.60
pages 233-249

MODELING THE HEALING OF MICROCRACKS IN METAL STIMULATED BY A PULSED HIGH-ENERGY ELECTROMAGNETIC FIELD. PART I

Konstantin V. Kukudzhanov
Institute for Problems in Mechanics, Russian Academy of Sciences, 101 Vernadsky Ave., bld. 1, Moscow, 119526, Russia; Moscow Institute of Physics and Technology, 9 Institutskiy Lane, Dolgoprudny, Moscow Region, 141700, Russia
Alexander L. Levitin
Institute for Problems in Mechanics, Russian Academy of Sciences, 101 Vernadsky Ave., bld. 1, Moscow, 119526, Russia

ABSTRAKT

The processes occurring in metallic specimens under the impact of electric high-density current are considered. The electric and temperature fields and their influence on the phase transformation and stress−strain state in the vicinity of microdefects in the form of plane cracks are studied. A mathematical model of the effect of an electromagnetic field on the predamaged elastic-plastic material with an ordered system of defects is proposed. The model accounts for melting and evaporation of material and the dependence of its all physical and mechanical properties on temperature. The problem is solved by finite elements method with the use of an adaptive mesh on the basis of an arbitrar Euler−Lagrange method. The numerical modeling has shown that in the vicinity of microdefects a high-density current with large field gradients arises, which leads to intense local heating accompanied by thermal expansion and melting of the metal on the tips of the microcracks. This results in high compressive stresses in the vicinity of microcracks, intense plastic flow of the material and, as a consequence, in the clamping of microcrack sides, decrease in microcrack length, and in the ejection of the molten material into the crack. As a result, the microcrack is completely healed. The numerical results obtained by the proposed model agree with experiment.