Decomposition and crystallization in a zirconium-based bulk amorphous alloy: effects on nuclear probes

Using Mossbauer spectroscopy with Fe-57 probes and perturbed angular correlations with ion implanted In-111-Cd-111 nuclear tracers, we have investigated decomposition and crystallization in the bulk amorphous alloys and Zr41.2Ti13.8Cu12.5Ni8.5(Fe-57)(1.5)Be-22.5 and Zr41.2Ti13.8Cu12.5Ni10Be22.5, respectively. Mossbauer and angular correlation spectra measured during the course of isothermal annealings at typical decomposition temperatures reveal distributions of quadrupole splittings as expected for an amorphous state, but no clear signs of crystallinity. A comparison of both experiments including the measured hyperfine parameters suggests that the Fe and Cd nuclei probe subsets of local environments which are clearly distinct from each other. We conclude that the Fe-57 probe has a clear sensitivity to decomposition processes whereas the In-111 tracers are insensitive to these phenomena in the studied case.