Localized Structural Instability and Dynamic Strength of Brittle Materials
Yu. I. Meshcheryakov, A. K. Divakov, N. I. Zhigacheva, G. V. Konovalov
Institute of Problems of Mechanical Engineering, Russian Academy of Sciences, Saint-Petersburg, 199178, Russia
Keywords: ударные испытания, локализованное хрупкое разрушение, откольная прочность, shock tests, localized brittle fracture, spall strength
Abstract
Four brittle materials are subjected to shock tests: gabbrodiabase, two modifications of cast iron, melted quartz, and beryllium. An interferometer is used to locally probe a free surface in order to calculate its velocity, thereby determining the criterion of the initial stage of brittle fracture of all materials tested - the formation of horizontal steps at the forefront of a compression pulse, which indicate the presence of local sources of fracture of the material. It is determined that the brittle material resists the shock compression as long as it has the reversible transfer of momentum and energy of the processes occurring at meso- and macrolevels.
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