Statistical features of magnetic noise in mixedtype impact fracture
Abstract
We study the statistical features of magnetic noise accompanying the dynamic fracture of steel samples during mixed type fracture, where the overall ductile character of crack propagation is interrupted by a sudden brittle jump. The structure of the voltage time series is investigated by identifying discrete peaks which correspond to elementary steps of the jerky cracking process. We show that the height, duration, area, and energy of peaks have power law distributions with exponents falling close to the corresponding values of pure ductile fracture. For single peaks, a power law correlation of the height and area with the width is evidenced; however, the mixed nature of fracture gives rise to a crossover between two regimes of different exponents. The average pulse shape of microcracking events has a parabolic form with a right handed asymmetry similarly to quasistatic fracture propagation. The asymmetry emerges due to stress localization at the advancing crack front.
 Authors:
 Department of Theoretical Physics, University of Debrecen, P.O. Box 5, H4010 Debrecen (Hungary)
 Bay Zoltán Nonprofit Ltd. for Applied Research, H1116 Budapest, Fehérvári út 130 (Hungary)
 Publication Date:
 OSTI Identifier:
 22412637
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 6; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ASYMMETRY; BRITTLENESS; CORRELATIONS; CRACK PROPAGATION; CRACKING; CRACKS; ELECTRIC POTENTIAL; FRACTURES; MAGNETISM; PULSE SHAPERS; STEELS; STRESSES
Citation Formats
Danku, Zs., Kun, F., Email: ferenc.kun@science.unideb.hu, and Lenkey, Gy. B.. Statistical features of magnetic noise in mixedtype impact fracture. United States: N. p., 2015.
Web. doi:10.1063/1.4908184.
Danku, Zs., Kun, F., Email: ferenc.kun@science.unideb.hu, & Lenkey, Gy. B.. Statistical features of magnetic noise in mixedtype impact fracture. United States. doi:10.1063/1.4908184.
Danku, Zs., Kun, F., Email: ferenc.kun@science.unideb.hu, and Lenkey, Gy. B.. 2015.
"Statistical features of magnetic noise in mixedtype impact fracture". United States.
doi:10.1063/1.4908184.
@article{osti_22412637,
title = {Statistical features of magnetic noise in mixedtype impact fracture},
author = {Danku, Zs. and Kun, F., Email: ferenc.kun@science.unideb.hu and Lenkey, Gy. B.},
abstractNote = {We study the statistical features of magnetic noise accompanying the dynamic fracture of steel samples during mixed type fracture, where the overall ductile character of crack propagation is interrupted by a sudden brittle jump. The structure of the voltage time series is investigated by identifying discrete peaks which correspond to elementary steps of the jerky cracking process. We show that the height, duration, area, and energy of peaks have power law distributions with exponents falling close to the corresponding values of pure ductile fracture. For single peaks, a power law correlation of the height and area with the width is evidenced; however, the mixed nature of fracture gives rise to a crossover between two regimes of different exponents. The average pulse shape of microcracking events has a parabolic form with a right handed asymmetry similarly to quasistatic fracture propagation. The asymmetry emerges due to stress localization at the advancing crack front.},
doi = {10.1063/1.4908184},
journal = {Applied Physics Letters},
number = 6,
volume = 106,
place = {United States},
year = 2015,
month = 2
}

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