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2017 №03 (07) DOI of Article
10.15407/tdnk2017.03.01
2017 №03 (02)


Technical Diagnostics and Non-Destructive Testing, №3, 2017 pp.3-13


Accumulation of damages in materials during fracture

C.A. Nedoseka, A. Ya. Nedoseka, L. I. Markashova, O. S. Kushnareva


E.O.Paton Electric Welding Institute of the NAS of Ukraine, 11, Kazimir Malevich str., 03150, Ukraine. E-mail: office@paton.kiev.ua

The article deals with regularities of occurrence and propagation of damages in materials during their deformation. As an example, the change in the structure of the specimen of steel 12Kh1MF under tension is considered in detail. It is shown that the process of accumulation of damages begins with occurrence of plastic deformations, stimulating an intensive movement and clustering of dislocations. Further, micro-discontinuities are formed, gradually transforming into pores, which propagate and join into larger formations. The process of damage appearance is well enough registered by applying the existing technology based on the acoustic emission method. This allows establishing the beginning of damages formation and their propagation up to the fracture. The analytical part of the technology makes it possible to plot the model of accumulation of damages and fracture. 20 – Ref., 1 – Table, 13 – Fig.
Key words: acoustic emission, plastic deformation, structure, pores, accumulation of damages
References
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