title: Texture of nanocrystalline nickel: probing the lower size limit of dislocation activity.
abstract: The size of nanocrystals provides a limitation on dislocation activity and associated stress-induced deformation. Dislocation-mediated plastic deformation is expected to become inactive below a critical particle size, which has been proposed to be between 10 and 30 nanometers according to computer simulations and transmission electron microscopy analysis. However, deformation experiments at high pressure on polycrystalline nickel suggest that dislocation activity is still operative in 3-nanometer crystals. Substantial texturing is observed at pressures above 3.0 gigapascals for 500-nanometer nickel and at greater than 11.0 gigapascals for 20-nanometer nickel. Surprisingly, texturing is also seen in 3-nanometer nickel when compressed above 18.5 gigapascals. The observations of pressure-promoted texturing indicate that under high external pressures, dislocation activity can be extended down to a few-nanometers-length scale.
authors.affiliation: Advanced Light Source, Lawrence Berkeley National Lab, Berkeley, CA 94720, USA. bchen@lbl.gov
authors.forename: Bin
authors.initials: B
authors.lastname: Chen
authors.forename: Katie
authors.initials: K
authors.lastname: Lutker
authors.forename: Selva Vennila
authors.initials: SV
authors.lastname: Raju
authors.forename: Jinyuan
authors.initials: J
authors.lastname: Yan
authors.forename: Waruntorn
authors.initials: W
authors.lastname: Kanitpanyacharoen
authors.forename: Jialin
authors.initials: J
authors.lastname: Lei
authors.forename: Shizhong
authors.initials: S
authors.lastname: Yang
authors.forename: Hans-Rudolf
authors.initials: HR
authors.lastname: Wenk
authors.forename: Ho-Kwang
authors.initials: HK
authors.lastname: Mao
authors.forename: Quentin
authors.initials: Q
authors.lastname: Williams