Viscous surface flow induced on Ti-based bulk metallic glass by heavy ion irradiation

Abstract

a b s t r a c tTi-based bulk metallic glass was irradiated by a 20 MeV Cl 4+ ion beam under liquid-nitrogen cooling, which produced remarkable surface smoothing and roughening that respectively correspond to normal and off-normal incidence angles of irradiation. Atomic force microscopy confirms two types of periodic ripples distributed evenly over the rough glass surface. In terms of mechanism, irradiation-induced viscosity agrees with the theoretical prediction for metallic glasses near glass transition temperature. Here, a model is introduced, based on relaxation of confined viscous flow with a thin liquid-like layer, that explains both surface smoothing and ripple formation. This study demonstrates that bulk metallic glass has high morphological instability and low viscosity under ion irradiation, which assets can pave new paths for metallic glass applications.

Effects of Heavy Ion Irradiation on the Thermoelectric Properties of In2(Te1−xSex)3 Thin Films

“…However, it decreased to ~27 nm and ~24 nm in 1E12 and 1E13, respectively. Thus, AFM studies proved surface smoothening as the ion fluence increased, possibly because of irradiation-induced viscous flow in the sample, as explained by Zhang et al, on Ti-based bulk metallic glass by heavy ion irradiation [ 35 ]. Further, the mean surface roughness became reduced with an increasing 20 MeV Cl 4+ ion dose, which confirmed the smoothing of surfaces.…”

Whiskers growth and self-healing in Ti-based metallic glasses during ion irradiation

“…The surface-confined viscous flow has been proven to play the dominant quantitative role during ion irradiation. This is caused by radiation-induced softening of the near-surface layer [11,23]. The origin of the softened region is caused by the rearrangements of atoms in certain structurally weak spots that behave as the liquid-like zone or the free volume.…”

“…Many studies focus on the intrinsic irradiation responses by MGs, including damage morphology [6], enhanced mechanical performance [7], and local structure change [8,9]. Studies have shown that the ion beam resistance capability of MGs is better than either their corresponding crystalline counterparts or traditional radiation-resistant materials [10,11]. The entirely disordered structure is considered a desirable environment to relax the damage induced by radiation as well as local shear stress.…”

Helium ions irradiation-induced surface damage in Fe-based melt-spun ribbons

“…Bulk metallic glasses (MG) have attracted great interest in recent decades for its unique mechanical and chemical properties such as high strength, large elastic strain and high corrosion resistance [1][2][3][4][5][6]. Due to their inherent disordered structure, they are supposed to be ideal potential candidates for application in nuclear-irradiated environments or deep space.…”