Affiliation:
1. The Federal research center Institute of Applied Physics of the Russian Academy of Sciences
2. National Research Lobachevsky State University of Nizhny Novgorod
Abstract
Analytical expressions are obtained for the configuration force and the value of elastic energy relaxation at the nucleation of a microcrack in a small neighborhood of an arbitrary singular stress source. When analyzing the conditions of crack nucleation at sources with weak divergences of the stress fields, ideas about the instantaneous nucleation of a crack of finite length are used. Simultaneous fulfillment of stress and energy conditions is considered as a criterion for the nucleation of such a crack. Within the framework of these representations, in the configuration space of the system parameters (geometric characteristics and strength of mesodefects, the value of external stress), the regions in which crack nucleation is possible in the case of a combined mesodefect, which is a superposition of the dipole of wedge disclinations and planar shear mesodefect, are determined. It is shown that the nucleation of the crack is significantly facilitated by the instability of the shear mesodefect.
Publisher
The Russian Academy of Sciences
Reference40 articles.
1. Рыбин В.В. Большие пластические деформации и разрушение металлов. М.: Металлургия, 1986. 224 с.
2. Рыбин В.В., Зисман А.А., Золоторевский Н.Ю. Стыковые дисклинации в пластически деформируемых кристаллах // ФТТ. 1985. Т. 27. № 1. С. 181–186.
3. Rybin V.V., Zisman A.A., Zolotorevsky N.Yu. Junction disclinations in plastically deformed crystals // Acta Metall. Mater. 1993. V. 41. № 7. P. 2211–2217.
4. Владимиров В.И., Романов А.Е. Дисклинации в кристаллах. Л.: Наука, 1986. 224 с.
5. Enikeev N.A., Orlova T.S., Alexandrov I.V., Romanov A.E. A physical criterion on grain subdivision during SPD // Solid State Phenomena. 2005. V. 101–102. P. 319–324.