Atomistic study of structural fluctuations during radiation-induced amorphization in the ordered intermetallic compound NiTi

We have carried out an atomistic study of electron-induced amorphization of an ordered intermetallic compound NiTi by means of in-situ high-resolution high-voltage electron microscopy observations and molecular dynamics simul ations. Both theoretical and experimental results show that metastable nano metre-size atomic clusters form and disappear during irradiation, so that a spatiotemporal fluctuation under amorphization is induced. Mean-lifetime m easurements of these clusters demonstrate that high-energy particle irradia tion provides a useful tool to study dynamic fluctuations of the local atom ic structure in the non-equilibrium open systems.