Behavior of Fatigue Cracks Generated from a Small Artificial-Defect in Plain Specimen of Copper Processed by Equal Channel Angular Pressing

Abstract:

Fatigue tests of ultrafine-grained copper processed by equal channel angular pressing were conducted on the round-bar specimens with a small artificial-defect. The fatigue crack initiated from the defect at an early fatigue stage. After the crack initiation, the crack grew with a 45° inclination to the loading axis at stress amplitudes above 180 MPa. At the stress less than 160 MPa, however, the crack grew perpendicular to the loading axis. The physical background of deferent crack path directions between high-and low-stresses was discussed from the viewpoint of a morphological feature of damaged traces along the crack path.

• Periodical: Materials Science Forum (Volume 941)
• Pages: 614-619
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.941.614
• Online since: December 2018
• Authors: Masahiro Goto, Takashi Iwamura, Takaei Yamamoto, S.Z. Han, Junichi Kitamura, Terutoshi Yakushiji
• Keywords: Copper, Crack Propagation, Equal Channel Angular Pressing, Fatigue

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