Stability of ultrafine-grained structure of copper under fatigue loading

0361143 - ÚFM 2012 RIV NL eng J - Journal Article
Kunz, Ludvík - Lukáš, Petr - Pantělejev, L. - Man, O.
Stability of ultrafine-grained structure of copper under fatigue loading.
Procedia Engineering. Roč. 10, - (2011), s. 201-206. E-ISSN 1877-7058
R&D Projects: GA ČR GAP108/10/2001
Institutional research plan: CEZ:AV0Z20410507
Keywords : fatigue of ultrafine-grained Cu * stability of ultrafine-grained structure * cyclic slip bands * shear bands
Subject RIV: JL - Materials Fatigue, Friction Mechanics

Stability of microstructure of ultrafine-grained materials under cyclic loading is a crucial condition for their good fatigue performance. Changes of microstructure due to fatigue in bulk, localization of cyclic plasticity into cyclic slip bands and related development of microstructure were experimentally studied on ultrafine-grained copper prepared by equal channel angular pressing. Different reaction of ultrafine-grained structure to plastic strain-controlled and load-controlled tests was found. The different susceptibility to dynamic grain coarsening under load and plastic strain-controlled tests reported in literature cannot be explained by differences in purity or details of equal channel angular pressing. The localization of the cyclic plasticity and the development of cyclic slip bands resulting in fatigue crack initiation take place in material volumes which can be characterized as “near by oriented” regions.
Permanent Link: http://hdl.handle.net/11104/0198537