Impact of deuterium plasma ions on mirror samples fabricated from Zr48Cu36Al8Ag8 and Zr57Cu15.4Al10Ni12.6Nb5 amorphous alloys

Abstract

Samples of two kinds of bulk metallic glasses (BMG) with different compositions, Zr48Cu36Al8Ag8 and Zr57Cu15.4Al10Ni12.6Nb5, were polished to mirror-like quality and, after measuring the initial reflectance at normal light incidence, were subjected to impact of ions of deuterium or argon plasma with fixed energy. The main attention was paid to phenomenon on deuterium absorption that reveals as the weight gain after every exposure of the samples in deuterium plasma. For a fixed ion energy (in the range<100 eV), the amount of absorbed deuterium increased linearly with increasing of the ion fluence. Bending of the samples was observed when one side of sample was bombarded by deuterium plasma ions. At that, the radius of curvature of samples was decreasing with increasing the amount of trapped deuterium in such a way that its curvature was increasing proportionally to the amount of trapped deuterium. This is an evidence of near-surface distribution of the trapped deuterium. The results demonstrate that D ions within a fluence of ∼2·1025 ions/m2 are initially accumulated in a thin near-surface layer of the samples. Further, they are noted effects of stress relaxation and of deuterium redistribution.