Structural Transformations in Ni at the Implantation C+ Ions

Abstract

Structural transformations in nickel films exposed to C+ ions were investigated through the use of electron diffraction and electron microscopy.

With an increasing exposure dose, there occurred a smooth transition of the FCC structure of Ni with lattice parameter а=0.352 to the HCP structure of carbide Ni3C with the lattice parameters a=0.266 nm and c=0.433 nm. The completion of the transition was observed once the implanted carbon concentration corresponding to the stoichiometry ratio of Ni3C was attained, this giving evidence for the chemical nature of the structural change observed. However, recognising that atoms of the composite do not form chemical compounds, it is possible to draw a conclusion that atoms of carbon form hexagonal structure and promote reorganisation of atoms of nickel in structure HCP. Thus of introduction atoms carry out a prevailing role in formation of the composite structure.