Project detail

Nové přístupy k výzkumu únavového šíření trhliny v módech II,III a II+III

Duration: 01.01.2010 — 31.12.2013

Funding resources

Czech Science Foundation - Standardní projekty

- whole funder (2010-01-01 - 2013-12-31)

On the project

Současné znalosti o podmínkách stability a šíření únavových trhlin zatěžovaných v módech II, III a II+III jsou velmi malé ve srovnání se znalostmi pro případ módu I. Cílem projektu jsou nové přístupy k výzkumu chování smykových trhlin, umožňující hlubší poznání mikromechanismů šíření. Budou provedeny únavové zkoušky na feritických a austenických ocelích pomocí původních zařízení, umožňujících současné šíření všech typů smykových trhlin v jediném vzorku. 3D fraktografické analýzy budou realizovány pomocístereofotogrammetrie a optické chromatografie. Rozsáhlé modelování poškozovacích procesů na čele trhliny metodami 3D molekulární dynamiky umožní získat multiskluzový obraz dislokací a zlepšit tak klasické dislokační modely. 3D elastoplastické numerické analýzy vzorků s trhlinami povedou ke stanovení křivek rychlosti šíření trhlin v celém rozsahu zbytkové životnosti. Tímto způsobem bude dosaženo přímé návaznosti výsledků projektu na inženýrské aplikace.

Description in English
A general knowledge about stability and growth conditions of fatigue cracks loaded under modes II, III and II+III is rather poor when compared to the mode I loading case. The project aims to apply new approaches to investigation of shear-mode cracks in order to better understand the crack-growth micromechanisms. Fatigue tests on ferritic and austenic steels will be accomplished by means of original devices designed for simultaneous crack growth under all shear modes in a single specimen will be utilized. The stereophotogrammetry and the optical chromatography will be applied to 3D fractographical analyses. An extended modelling of damage processes at the crack front will be performed by means of the 3D molecular dynamics to obtain a multi-slip picture of dislocations in order to improve the classical dislocation models. A 3D elastic-plastic numerical analyses of cracked specimens will be executed in order to determine crack growth rate curves in the whole range of the residual fatigue life.

Keywords
šíření únavové trhliny, experiment, modelování

Key words in English
fatigue crack growth; experiments; modelling

Mark

GAP108/10/0698

Default language

Czech

People responsible

Machová Anna, Ing., CSc. - fellow researcher
Pokluda Jaroslav, prof. RNDr., CSc. - principal person responsible

Units

Institute of Physical Engineering
- (2010-01-01 - 2013-12-31)
Institute of Thermomechanics Academy of Sciences of the Czech Republic
- (2010-01-01 - 2013-12-31)

Results

HORNÍKOVÁ, J.; ŠANDERA, P.; POKLUDA, J. Stress Intensity Factors for Surface Semi-elliptical Crack in Cylindrical Specimen under Combined Torsion and Axial Compression. Key Engineering Materials (print), 2011, vol. 452-453, no. 1, p. 673-676. ISSN: 1013-9826.
Detail

LANDA, M.; MACHOVÁ, A.; UHNÁKOVÁ, A.; POKLUDA, J.; LEJČEK, P. Crack growth in Fe–2.7 wt% Si single crystals under cyclic loading and 3D atomistic results in bcc iron. INTERNATIONAL JOURNAL OF FATIGUE, 2016, vol. 87, no. 1, p. 63-70. ISSN: 0142-1123.
Detail

UHNÁKOVÁ, A.; POKLUDA, J.; MACHOVÁ, A.; HORA, P. 3D Atomistic Simulation of Fatigue Behaviour of Cracked Single Crystal of bcc Iron Loaded in Mode III. INTERNATIONAL JOURNAL OF FATIGUE, 2011, vol. 33, no. 1, p. 1564-1573. ISSN: 0142-1123.
Detail

VOJTEK, T. Šíření únavových trhlin v módu II a III v oblasti prahových hodnot ve feritické a austenitické oceli. In TechMat 11. Pardubice: Univerzita Pardubice, 2011. s. 117-122. ISBN: 978-80-7395-431-4.
Detail

UHNÁKOVÁ, A.; POKLUDA, J.; MACHOVÁ, A.; HORA, P. 3D Atomistic Simulation of Fatigue Behavior of a Ductile Crack in BCC Iron loaded in mode II. COMPUTATIONAL MATERIALS SCIENCE, 2012, vol. 61, no. 1, p. 12-19. ISSN: 0927-0256.
Detail

VOJTEK, T.; POKLUDA, J.; HORNÍKOVÁ, J.; ŠANDERA, P.; HOHENWARTER, A.; PIPPAN, R. Equivalent K-factor for Near-threshold Mode II+III Fatigue Crack Growth in ARMCO Iron. Oxford: 2012.
Detail

VOJTEK, T.; POKLUDA, J.; ŠANDERA, P.; HORNÍKOVÁ, J.; SLÁMEČKA, K.; PIPPAN, R.; HOHENWARTER, A. Near-threshold Fatigue Crack Propagation under Mixed-mode II+III in ARMCO Iron. In 19th European Conference on Fracture. Kazan: 2012. p. 188-193. ISBN: 978-5-905576-18-8.
Detail

VOJTEK, T.; POKLUDA, J. Paths of Shear-mode Cracks in Ferritic and Austenitic Steel. In Proceedings of the 4th International Conference on Crack Paths (CP 2012). Parma: 2012. p. 727-734. ISBN: 9788895940441.
Detail

VOJTEK, T.; POKLUDA, J.; HOHENWARTER, A.; PIPPAN, R. Evaluation of Near-Threshold Fatigue Crack Propagation under Mixed Mode II+III in ARMCO Iron. Brno: Institute of Physics of Materials, 2012. ISBN: 978-80-87434-05-5.
Detail

SLÁMEČKA, K.; KIANICOVÁ, M.; POKLUDA, J. Fractographically-aided Analysis of Fish-eye Crack Growth in Nitrided Steel. Journal of Theoretical and Applied Mechanics, 2013, vol. 51, no. 2, p. 439-446. ISSN: 1429-2955.
Detail

VOJTEK, T.; POKLUDA, J.; HOHENWARTER, A.; PIPPAN, R. Three-dimensional morphology of fracture surfaces generated by mode II and III fatigue loading in ferrite and austenite. Engineering Fracture Mechanics, 2013, vol. 108, no. 1, p. 285-293. ISSN: 0013-7944.
Detail

ČERNÝ, M.; ŠESTÁK, P.; POKLUDA, J.; ŠOB, M. Shear instabilities in perfect bcc crystals during simulated tensile tests. PHYSICAL REVIEW B, 2013, vol. 87, no. 1, p. 014117-014117. ISSN: 1098-0121.
Detail

VOJTEK, T.; PIPPAN, R.; HOHENWARTER, A.; HOLÁŇ, L.; POKLUDA, J. Near-threshold propagation of mode II and mode III fatigue cracks in ferrite and austenite. Acta materialia, 2013, vol. 61, no. 12, p. 4625-4635. ISSN: 1359-6454.
Detail

SLÁMEČKA, K.; POKLUDA, J.; KIANICOVÁ, M.; HORNÍKOVÁ, J.; OBRTLÍK, K. Fatigue Life of Cast Inconel 713LC with/without Protective Diffusion Coating under Bending, Torsion and their Combination. Engineering Fracture Mechanics, 2013, vol. 110, no. 1, p. 459-467. ISSN: 0013-7944.
Detail

HORNÍKOVÁ, J.; ŽÁK, S.; ŠANDERA, P. K-calibration of Special Specimens for Mode II, III and II+III Crack Growth. Engineering Fracture Mechanics, 2013, vol. 110, no. 1, p. 430-437. ISSN: 0013-7944.
Detail

VOJTEK, T.; POKLUDA, J. Experimental Investigation of Modes II and III Fatigue Crack Growth in Unalloyed Titanium. 7th International Conference on Materials Structure & Micromechanics of Fracture. 2013. p. 179-179. ISBN: 978-80-214-4739-4.
Detail

VOJTEK, T.; POKLUDA, J.; HOHENWARTER, A.; PIPPAN, R. Propagation of Long Fatigue Cracks under Remote Mode II, III and II+III in Metals. 13th International Conference on Fracture (ICF13). Beijing: 2013. p. 86-86. ISBN: 978-988-12-2652-5.
Detail

POKLUDA, J.; PIPPAN, R.; VOJTEK, T.; HOHENWARTER, A. Near-threshold behaviour of shear-mode fatigue cracks in metallic materials. Fatigue & Fracture of Engineering Materials & Structures, 2014, vol. 37, no. 3, p. 232-254. ISSN: 8756-758X.
Detail

HORNÍKOVÁ, J.; ŠANDERA, P.; ŽÁK, S.; POKLUDA, J. Specimens for Simultaneous Mode II, III and II+III Fatigue Crack Propagation: Elasto-Plastic Solution of Crack Tip Stress-Strain Field. In 11TH INTERNATIONAL FATIGUE CONGRESS. Advanced Materials Research. 1. Melbourne: Trans Tech Publications, 2014. p. 1585-1590. ISBN: 978-3-03835-008-8. ISSN: 1022-6680.
Detail

HORNÍKOVÁ, J.; ŠANDERA, P.; ŽÁK, S.; POKLUDA, J. Elasto-plastic Solution of Stress-strain Field at the Crack Tip in Special Specimens for Mode II, III and II+III Fatigue Crack Propagation. Euromat 2013. 1. Sevilla: Barceló Congresos, 2013. p. 617-617.
Detail

HORNÍKOVÁ, J.; ŠANDERA, P.; ŽÁK, S. Elasto-Plastic Solution of Stress-Strain Field at the Crack Tip in Special Specimens for Mode II, III and II+III Fatigue Crack Propagation. Materials Structure & Micromechanics of Fracture (MSMF7). 1. Brno: Vutium, 2013. p. 194-194. ISBN: 978-80-214-4739-4.
Detail

HORNÍKOVÁ, J.; ŽÁK, S.; ŠANDERA, P. K-calibration of Special Specimen for Mode II, III and II+III Crack Growth. 8th Meeting of the TC2 on Micromechanisms (ESIS). 1. Oxford: Mansfield College, 2012. p. 35-35.
Detail

POKLUDA, J. Theoretical Strength of Solids: A Bridge from Interatomic Bonds to Local Plasticity and Fracture. Cambridge: ESIS, 2012. p. 21-26.
Detail

MACHOVÁ, A.; POKLUDA, J.; UHNÁKOVÁ, A.; HORA, P. 3D Atomistic Studies of Fatigue Behavior of Edge Crack (001) in BCC Iron loaded in mode I and II. INTERNATIONAL JOURNAL OF FATIGUE, 2014, vol. 66, no. 1, p. 11-19. ISSN: 0142-1123.
Detail

VOJTEK, T.; POKLUDA, J.; ŠANDERA, P.; HORNÍKOVÁ, J.; HOHENWARTER, A.; PIPPAN, R. Analysis of fatigue crack propagation under mixed mode II + III in ARMCO iron. INTERNATIONAL JOURNAL OF FATIGUE, 2015, vol. 76, no. 1, p. 47-52. ISSN: 0142-1123.
Detail

VOJTEK, T. Experiments on Fatigue Crack Propagation in Loading Modes II and III in Metals. In 13th Conference Applied mechanics 2011. Brno: 2011. p. 239-242. ISBN: 978-80-87434-03-1.
Detail

Responsibility: Pokluda Jaroslav, prof. RNDr., CSc.