Microstructural examination of Ni-ion irradiated Fe-Ni-Cr alloys followed to micro-zone deformation

Examination of deformation microstructures induced by micro-indentation tec hnique by means of transmission electron microscopy (TEM) following an MV r ange metallic ion irradiation was performed in order to study the influence of irradiation-produced microstructural defects on plastic deformation beh avior of materials. In this work, specimens of an Fe-Cr-Ni austenitic model ternary alloy before and after irradiation with 4 MeV Ni ions at 723 K wer e indentation-tested at loads as low as 9.8 mN using an instrumented micro- indentation testing system. The dislocation microstructures of the specimen s' regions beneath the indents were successfully examined with a TEM follow ing a cross-sectional thin film processing with a focused ion beam (FIB) pr ocessing system. This paper describes the experimental procedure developed in this study and the results from the first series of the experiments. (C) 1999 Published by Elsevier Science B.V. All rights reserved.