The Effect of Ion Irradiation on Nanocrystallization and Surface Relief of a Ribbon from Fe 72.5 Cu 1 Nb 2 Mo 1.5 Si 14 B 9 Alloy

Using the methods of X-ray diffraction and atomic force microscopy, the process of crystallization of an amorphous Fe 72.5 Cu 1 Nb 2 Mo 1.5 Si 14 B 9 alloy irradiated with accelerated Ar + ions is investigated. It is found out that an irradiation by the Ar + ions with the energy 30 keV at the ion current density 300 μA/cm 2 (fluence 3.75·10 15 cm –2 , irradiation time ~2 s, ion-beam short-duration heating up to 350°С, which is 150°С lower than the thermal crystallization threshold) results in a complete crystallization of this amorphous alloy (throughout the bulk of a 25 μm ribbon) followed by precipitation of solid solution crystals of α-Fe(Si), close in its composition to Fe 80 Si 20 , stable phase of Fe 3 Si, and metastable hexagonal phases. By the methods of atomic force and scanning tunneling microscopy it is shown that nanocrystallization caused by ion irradiation is accompanied by surface relief changes both on the irradiated and unirradiated sides of the Fe 72.5 Cu 1 Nb 2 Mo 1.5 Si 14 B 9 alloy ribbon at the depth exceeding by a factor of 10 3 that of the physical ion penetration for this material. The data obtained, taking into account a significant temperature decrease and multiple acceleration of the crystallization process, serve an evidence of the radiation-dynamic influence of accelerated ions on the metastable amorphous medium.