Effects of P Content on Nanocrystalline Morphology Formed by FIB Irradiation in Ni-P Amorphous Alloy

Abstract

We studied the effects of phosphorus (P) on the Ni nanocrystalline morphology of Ni-P amorphous alloy thin films subjected to focused ion beam (FIB) irradiation. The P contents in the amorphous alloys varied from 14 to 20 at%. The nanocrystals induced by FIB irradiation of Ni-20.2, 15.6, and 14.0 at%P amorphous alloys had a face-centered-crystal (f.c.c.) structure and showed unique crystallographic orientation relationships to the geometry of the focused ion beam, with {111} f.c.c. parallel to the irradiated plane and h110i f.c.c. parallel to the direction of the projected ion beam, respectively. The Ni nanocrystals formed by FIB irradiation precipitated in the same manner as aggregates, and the average size of the Ni nanocrystals increased as the P content decreased. These results indicate that the P content does not affect the crystallographic orientation relationships but does influence precipitation distribution of the Ni nanocrystals