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Title of the article IMPACT INDENTATION OF METALS AT THE SMALL ELASTOPLASTIC STRAIN
Authors

KREN Alexander P., D. Sc. in Eng., Assoc. Prof., Head of the Laboratory of Contact-Dynamic Control Methods, Institute of Applied Physics of the NAS of Belarus, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it.
In the section MATERIALS SCIENCE IN MECHANICAL ENGINEERING
Year 2022
Issue 1(58)
Pages 56–63
Type of article RAR
Index UDK 620.17, 539.3
DOI https://doi.org/10.46864/1995-0470-2022-1-58-56-63
Abstract The aim of this paper is to study and describe the behavior features of metals under impact loading in the area of elastic-plastic transition, with strains not exceeding 3–4 %, which are typical for measuring the hardness of materials during dynamic indentation. It has been established that until the state of full plasticity is reached, the excess of the dynamic hardness over the static one cannot be explained only by an increase of the strain rate and requires taking into account the elastic properties of the material. It is shown that a grow of the yield stress and the part of elastic deformation leads to a significant increase in the dynamic hardness of the material. This is due to the feature of measurements, which consists in fixing the value of the initial impact energy, which is distributed between elastic and plastic part of strain, depending on the characteristics of the material: yield stress, elastic modulus, strain-hardening coefficient.
Keywords indentation, metals, deformation, impact, elastoplasticity
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