Modification of the atomic structure of metallic materials after strong external exposures

Abstract

The paper presents the application of direct methods (field ion microscopy and atom probe techniques) to study the modification of the crystal structure of various materials at the atomic spatial level after strong external exposures. The effects of amorphization of subsurface volumes of alloys, deformation effects in pure metals, and structural phase transformations in subsurface volumes of solid solutions were detected during radiation exposure to charged particle beams with an energy of 20 keV. The original results show the possibility of three-dimensional reconstruction of the elemental composition of the materials investigated with atomic resolution to study the modification of the atomic structure. It is established that the nature of the crystalline structure of the boundary region of planar defects directly depends on the type of external influence. Experimental data on the elemental composition of interphase interfaces in mechanically alloyed compounds and doped alloys have been obtained. It is established that the width of the boundary regions at the metal interfaces varies within 0.8-1.5 nm, depending on the type of intensive external action to which they were subjected. © Published under licence by IOP Publishing Ltd.