〈a〉 Prismatic, 〈a〉 basal, and 〈c+a〉 slip strengths of commercially pure Zr by micro-cantilever tests. (1st September 2015)

• Record Type: Journal Article
• Authors: Gong, Jicheng; Benjamin Britton, T.; Cuddihy, Mitchell A.; Dunne, Fionn P.E.; Wilkinson, Angus J.
• Is Part Of: Acta materialia. Volume 96(2015)
• Page Start: 249
• Page End: 257
• Publication Date: 2015-09-01
• Subjects: Zirconium -- Micro-cantilever test -- Slip properties -- Anisotropy -- CRSS; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Mechanical properties -- Periodicals; Metallurgy -- Periodicals; Chemistry, Inorganic -- Periodicals; 620.112
• DOI: 10.1016/j.actamat.2015.06.020
• Languages: English
• ISSNs: 1359-6454

Abstract

Abstract: Slip strengths of 〈a〉 basal, 〈a〉 prism, and 〈c+a〉 pyramidal systems in commercially pure zirconium have been determined using micro-cantilever testing. A range of single crystal cantilevers 0.5 μm to 10 μm wide, oriented for single slip were prepared using focused ion beam (FIB) machining and subsequently deflected using a nanoindenter. The critical resolved shear stress ( τ crss ) was found by fitting a crystal plasticity finite element model to the experimental load–displacement data for these micro-bending tests. All the three slip systems in α-Zr show a marked size effect in bending described well by τ CRSS ( W ) = τ 0 + AW n, where W is the cantilever width, τ 0 is the CRSS at the macro scale and n = ∼−1. The exponent, n, of near −1 is in good accord with hardening caused by the back stress generated by dislocations piling up at a diffuse barrier caused by the reduction of stress near the neutral axis. The macro scale CRSS values were used to successfully simulate deformation of a conventional macroscopic compression test.