Ultrafine versus coarse grained Al 5083 alloys: From low-cycle to very-high-cycle fatigue. (April 2019)

• Record Type: Journal Article
• Authors: Meng, Li; Goyal, Anchal; Doquet, Véronique; Ranc, Nicolas; Couzinié, Jean-Philippe
• Is Part Of: International journal of fatigue. Volume 121(2019)
• Page Start: 84
• Page End: 97
• Publication Date: 2019-04
• Subjects: Cyclic plasticity -- VHCF -- Ultrafine grains -- Al-Mg alloy -- Fish-eye; Materials -- Fatigue -- Periodicals; Materials -- Fatigue; Periodicals; 620.1122
• DOI: 10.1016/j.ijfatigue.2018.12.004
• Languages: English
• ISSNs: 0142-1123

Abstract

Highlights: Ultrafine-grained 5083 Al alloy produced by ECAP exhibits cyclic hardening. At high plastic strain amplitude it shows easier crack initiation and a lower fatigue life. Its resistance to HCF is hardly better than that of its coarse grained counterpart. Between 2.10 6 and 5.10 8 cycles, its fatigue resistance is 43% higher. Beyond 5.10 8 cycles internal crack initiation occurs and the resistance of the UFG material decreases. Abstract: The fatigue performance of coarse and ultrafine-grained (UFG) 5083 Al alloy were compared, from low to very high cycle fatigue. The UFG alloy exhibited cyclic hardening and predominant kinematic hardening. At high plastic strain amplitude (and only in this regime), it showed easier crack initiation and a lower fatigue resistance. Its resistance to HCF was hardly better than that of its coarse grained counterpart until 2.10 6 cycles, but 43% higher in VHCF, until 5.10 8 cycles. Beyond that point, internal crack initiation occurred, and the fatigue resistance of the UFG material decreased, which was explained using Fracture Mechanics.