A. Benyagoub et al., CREEP OF A CRYSTALLINE METALLIC LAYER INDUCED BY HIGH-ENERGY HEAVY-ION IRRADIATION, Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms, 107(1-4), 1996, pp. 189-193
The atomic transport induced by ion electronic energy loss in amorphou
s systems is studied on metallic sandwiches irradiated at liquid nitro
gen temperature with 500 MeV iodide ions delivered by the VICKSI accel
erator of the Hahn-Meitner-Institut (Berlin), The sandwiches are compo
sed of two amorphous Ni3B layers of 1 or 1.5 mu m thickness embedding
a crystalline Au or W layer of thickness varying from 20 to 900 nm, Ru
therford backscattering experiments using a 3.6 MeV He2+ beam delivere
d by the ARAMIS accelerator of the CSNSM (Orsay) were performed in ord
er to determine the modifications of the geometry of the sandwiches af
ter swift heavy ion irradiation, The results show a huge creep of the
crystalline part of the sandwiches. The magnitude of this creep depend
s on the nature of the crystalline layer (Au or W) and increases stead
ily with the irradiating ion fluence with a strain-rate decreasing wit
h increasing layer thickness. This creep phenomenon is due to the plas
tic deformation process occurring in the surrounding amorphous layers
and is induced by ion electronic energy loss, A simple rheological mod
el is developed to reproduce the observed effects.