Towards Quantitative Explanation of Effective Thresholds of Mode III Fatigue Crack Propagation in Metals

0512011 - ÚFM 2020 RIV CH eng C - Konferenční příspěvek (zahraniční konf.)
Vojtek, Tomáš - Žák, S. - Pokluda, J.
Towards Quantitative Explanation of Effective Thresholds of Mode III Fatigue Crack Propagation in Metals.
MECHANICAL FATIGUE OF METALS: EXPERIMENTAL AND SIMULATION PERSPECTIVES. Basel: SPRINGER NATURE SWITZERLAND AG, 2019 - (Correeia, J.; DeJesus, A.; Fernandes, A.; Calcada, R.), s. 161-167. Structural Integrity-Series, 7. ISBN 978-3-030-13980-3. ISSN 2522-560X.
[ICMFM 2019 - International Colloquium on Mechanical Fatigue of Metals /19./. Porto (PT), 05.09.2019-07.09.2019]
Grant CEP: GA MŠMT(CZ) LQ1601
Institucionální podpora: RVO:68081723
Klíčová slova: effective threshold * modes II and III * local growth mode * metals
Obor OECD: Audio engineering, reliability analysis

The article presents the state-of-the art of tools for prediction of mode I, II and III effective thresholds for metallic materials. The effective threshold is independent of the stress ratio as well as the yield strength and is, therefore, a universal parameter for a particular metal. It can also be also used to separate the effective and crack closure components of resistance to fatigue crack growth. Results of recent research provided relationships for quantification of mode II and mode III effective thresholds for a wide range of metallic materials which are in a good agreement with experiments. The local crack growth mode has to be taken into account which depends on crystal lattice type and secondary phase type. The mode III cracks propagate by local crack front advances under mode I or mode II which was taken into account in numerical calculation of local stress intensity factors. It allowed explanation of the experimentally obtained values of the mode III effective thresholds.
Trvalý link: http://hdl.handle.net/11104/0302512