Fatigue damage of ultrafine-grain copper in very-high cycle fatigue region

0361095 - ÚFM 2012 RIV CH eng J - Journal Article
Lukáš, Petr - Kunz, Ludvík - Navrátilová, Lucie - Bokůvka, O.
Fatigue damage of ultrafine-grain copper in very-high cycle fatigue region.
Materials Science and Engineering A Structural Materials Properties Microstructure and Processing. Roč. 528, - (2011), s. 7036-7040. ISSN 0921-5093. E-ISSN 1873-4936
R&D Projects: GA ČR GAP108/10/2001
Institutional research plan: CEZ:AV0Z20410507
Keywords : ultrafine-grained microstructure * ultrasonic fatigue * crack initiation * copper
Subject RIV: JL - Materials Fatigue, Friction Mechanics
Impact factor: 2.003, year: 2011

Ultrafine-grained copper produced by ECAP technique was tested in ultrasonic fatigue in the region of lives from 108 to 2x1010 cycles. The fatigue strength of ultrafine-grained copper is by a factor of 2 higher than that of conventional-grain copper. The occurrence of surface fatigue slip markings is rare. No grain coarsening was observed either in bulk or in areas underneath the surface slip markings. Localized collective grain-boundary slip of near-by oriented grains is considered to be the main damage mechanism leading to fatigue microcrack initiation either directly in the roots of surface intrusions or underneath the surface slip markings.
Permanent Link: http://hdl.handle.net/11104/0198502