Experimental study on the origin of crack initiation in fatigued metals

0399547 - ÚFM 2014 RIV DE eng C - Conference Paper (international conference)
Man, Jiří - Valtr, M. - Kuběna, Ivo - Petrenec, Martin - Obrtlík, Karel - Polák, Jaroslav
Experimental study on the origin of crack initiation in fatigued metals.
Proceedings of the Seventh International Conference on Low Cycle Fatigue - LCF7. Berlín: DMV, 2013, s. 391-396. ISBN 978-3-9814516-2-7.
[LCF7 - International Conference on Low Cycle Fatigue /7./. Aachen (DE), 09.09.2013-11.09.2013]
R&D Projects: GA ČR(CZ) GAP108/10/2371
Institutional support: RVO:68081723
Keywords : fatigue crack initiation * austenitic steel * polycrystalline copper * atomic force microscopy * persistent slip band
Subject RIV: JL - Materials Fatigue, Friction Mechanics

Early stages of surface relief evolution of persistent slip markings (PSMs) were studied by atomic force microscopy (AFM) and high-resolution scanning electron microscopy (SEM– FEG) on two polycrystalline materials – 316L austenitic stainless steel fatigued at 93 K, 173 K and 573 K and copper fatigued at 83 K, 173 K and 295 K. Experimental data on the morphology of PSMs, occurrence of extrusions and intrusions and the kinetics of extrusion growth are discussed with respect to the formation of point defects within areas of localized cyclic slip (persistent slip bands – PSBs) and especially to their mobility at different temperatures. The importance of mass redistribution due to the migration of respective type of point defects for PSM formation and creation of fatigue crack embryos, i.e. sharp intrusions is highlighted.
Permanent Link: http://hdl.handle.net/11104/0226834