Shock-induced localized amorphization in metallic nanorods with strain-rate-dependent characteristics.
Classical force-field simulations were used to study the tensile shock-induced response of metallic nanorods. The nanorods were found to amorphize at strain-rate amorphization limits of 1.6% ps(-1) for a 4.0-nm-diameter platinum (Pt) nanorod and 1.2% ps(-1) for a 4.0-nm-diameter gold (Au) nanorod, with a length-to-diameter ratio of 3. Highly localized necking was observed at mid-depth of the nanorods at about 2.0% ps(-1). As the strain rates were increased further, the neck bifurcated away from the mid-depth toward the nanorod ends, resulting in multiple necks at 4.0% ps(-1) and 3.0% ps(-1) for Pt and Au, respectively. At strain rates of above 6.0% ps(-1), end delamination took place. The longitudinal wave propagation equation was adequate to explain and predict the location of the appearance of necks along the nanorod.
Koh
Adrian S J
AS
Institute of High Performance Computing, 1 Science Park Road, #01-01, The Capricorn, Singapore Science Park II, Singapore. kohsj@ihpc.a-star.edu.sg
Lee
Heow-Pueh
HP
D016880:Anisotropy; D003198:Computer Simulation; D004548:Elasticity; D008670:Metals / Q000737:chemistry*; D008956:Models, Chemical; D008958:Models, Molecular; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D013314:Stress, Mechanical; D013718:Tensile Strength
D008670:Metals