Publication detail

Study of Initial Stages of Fatigue Process Using Non-destructive Testing Methods

VLAŠIC, F. VOLÁK, J. NOHÁL, L. MAZAL, P. HORT, F.

Original Title

Study of Initial Stages of Fatigue Process Using Non-destructive Testing Methods

Czech Title

Studium počátečních stádií únavového procesu využitím nedestruktivních metod testování

English Title

Study of Initial Stages of Fatigue Process Using Non-destructive Testing Methods

Type

journal article

Language

en

Original Abstract

This paper deals with the basic research of cyclic damage during the initial stages of fatigue process using the non-destructive testing methods. The acoustic emission method was used for monitoring of the microstructure changes during fatigue loading. The electrical potential measurements of specimen and microscopic observation were used mainly to detect the first short cracks and their propagation. The fatigue tests at room temperature were conducted on titanium alloy and creep-resistant steel specimens under bending and tension loading. The aim of the study was to compare the acoustic emission signal at different types of loading until fracture and to analyze in detail the signal changes in initial stages of fatigue process. This analysis was primarily based on the waveform similarity and division into classes. The results show the high sensitivity of the acoustic emission technology in the transition from the stage of surface relief evolution to the stage of crack nucleation and propagation.

Czech abstract

Tato práce se zabývá základním výzkumem cyklického poškozování počátečních stádií únavového procesu využitím nedestruktivních metod testování. Pro monitorování mikrostrukturních změn během únavového zatěžování byla využita metoda akustické emise. K detekci prvnch krátkých trhlin a jejich následnému šíření bylo využito měření elektrického potenciálu vzorku a mikroskopického pozorování. Únavové zkoušky za pokojové teploty byly realizovány na titanové slitině a žáropevné oceli při ohybovém a tahovém namáhání. Cílem bylo porovnat signál akustické emise při různém charakteru zatěžování až do lomu a podrobně zanalyzovat změny signálu v počátečních stádiích únavového procesu. Tyto analýzy byly založeny zejména na podobnosti tvaru vlny a následně rozděleny do jednotlivách tříd. Výsledky ukazují vysokou citlivost techniky akustické emise při přechodu z fáze vývoje povrchového reliéfu do fáze iniciace a šíření trhliny.

English abstract

This paper deals with the basic research of cyclic damage during the initial stages of fatigue process using the non-destructive testing methods. The acoustic emission method was used for monitoring of the microstructure changes during fatigue loading. The electrical potential measurements of specimen and microscopic observation were used mainly to detect the first short cracks and their propagation. The fatigue tests at room temperature were conducted on titanium alloy and creep-resistant steel specimens under bending and tension loading. The aim of the study was to compare the acoustic emission signal at different types of loading until fracture and to analyze in detail the signal changes in initial stages of fatigue process. This analysis was primarily based on the waveform similarity and division into classes. The results show the high sensitivity of the acoustic emission technology in the transition from the stage of surface relief evolution to the stage of crack nucleation and propagation.

Keywords

fatigue loading, acoustic emission signal, surface relief evolution, crack

RIV year

2014

Released

01.01.2014

Publisher

Trans Tech Publications

Location

Switzerland

Pages from

553

Pages to

556

Pages count

4

BibTex


@article{BUT100973,
  author="František {Vlašic} and Josef {Volák} and Libor {Nohál} and Pavel {Mazal} and Filip {Hort}",
  title="Study of Initial Stages of Fatigue Process Using Non-destructive Testing Methods",
  annote="This paper deals with the basic research of cyclic damage during the initial stages of
fatigue process using the non-destructive testing methods. The acoustic emission method was used
for monitoring of the microstructure changes during fatigue loading. The electrical potential
measurements of specimen and microscopic observation were used mainly to detect the first short
cracks and their propagation. The fatigue tests at room temperature were conducted on titanium
alloy and creep-resistant steel specimens under bending and tension loading. The aim of the study
was to compare the acoustic emission signal at different types of loading until fracture and to
analyze in detail the signal changes in initial stages of fatigue process. This analysis was primarily
based on the waveform similarity and division into classes. The results show the high sensitivity of
the acoustic emission technology in the transition from the stage of surface relief evolution to
the stage of crack nucleation and propagation.",
  address="Trans Tech Publications",
  chapter="100973",
  doi="10.4028/www.scientific.net/KEM.592-593.553",
  howpublished="print",
  institution="Trans Tech Publications",
  number="553",
  volume="592-593",
  year="2014",
  month="january",
  pages="553--556",
  publisher="Trans Tech Publications",
  type="journal article"
}