Publication detail
Fatigue crack propagation in steels for railway axles
NÁHLÍK, L. POKORNÝ, P. HUTAŘ, P. MATUŠEK, P.
Czech title
Šíření únavové trhliny v ocelích železničních náprav
English title
Fatigue crack propagation in steels for railway axles
Type
journal article in Web of Science
Language
en
Original abstract
The paper deals with the influence of order of cycles in the loading block on the fatigue crack growth rate in railway axle. The railway axle can include some cracks from manufacturing process or initiated fatigue cracks from previous operation. It is advantageous to know how the crack will behave during further service of the train to ensure its safe operation. The classical approaches describing the fatigue crack growth do not take into account the effects of overload cycles, which enlarge the plastic zone ahead of the crack tip. The enlarged plastic zone generates residual compressive stresses, which cause a retardation of the fatigue crack growth. Finite element numerical calculations were used together with the generalized Willenborg model to determine influence of overload cycles on the increment of fatigue crack growing in railway axles. Real geometry of the axle, the crack front shape and typical loading spectrum were taken into account.
Czech abstract
Vlakové nápravy jsou vystaveny proměnlivému zatěžování během provozu. Článek se zabývá vlivem pořadí zátěžných tříd amplitud napětí na velikost přírůstku délky trhliny za jeden zátěžný blok. Pro zahrnutí interakčních efektů byl použit zobecněný Willenborgův model. V článku jsou uvažovány dva často používané materiály pro železniční nápravy, oceli EA1N a EA4T.
English abstract
The paper deals with the influence of order of cycles in the loading block on the fatigue crack growth rate in railway axle. The railway axle can include some cracks from manufacturing process or initiated fatigue cracks from previous operation. It is advantageous to know how the crack will behave during further service of the train to ensure its safe operation. The classical approaches describing the fatigue crack growth do not take into account the effects of overload cycles, which enlarge the plastic zone ahead of the crack tip. The enlarged plastic zone generates residual compressive stresses, which cause a retardation of the fatigue crack growth. Finite element numerical calculations were used together with the generalized Willenborg model to determine influence of overload cycles on the increment of fatigue crack growing in railway axles. Real geometry of the axle, the crack front shape and typical loading spectrum were taken into account.
Keywords in Czech
vlaková náprava, retardační efekt, proměnné zatěžování, zobecněný Willinborgův model
Keywords in English
railway axle, crack retardation, variable loading amplitude, generalized Willenborg model.
RIV year
2014
Released
06.01.2014
ISSN
1013-9826
Volume
2014
Number
592-593
Pages from–to
254–257
Pages count
4
BIBTEX
@article{BUT101681,
author="Luboš {Náhlík} and Pavel {Pokorný} and Pavel {Hutař} and Petr {Matušek},
title="Fatigue crack propagation in steels for railway axles",
year="2014",
volume="2014",
number="592-593",
month="January",
pages="254--257",
issn="1013-9826"
}