One of the advantages of Atom Probe Field Ion Microscopy (APFIM) as compared to other nanoanalytical instruments is its very high spatial resolution and its quantitativity in composition measurement. A few tenths of a nanometer at the specimen surface as well as an ultimate depth resolution of one atomic resolution can routinely be attained. Among the numerous improvements brought about since its early developments in the seventies, the advent of three-dimensional atomprobes (see papers of G.D.W Smith and A. Cerezo, this issue) has been probably one of the most important breakthroughs, the Tomographic Atom Probe (TAP) being the French prototype [1]. As shown in a recent publication, this instrument is able to map out both composition and order 3D fields on a scale close to that of the unit cell [2], In this contribution, we shall focus on the application of 1D and 3D atom-probes to the study of nickel base superalloys.
ATOM-PROBE STUDY OF SOME FINE-SCALE FEATURES IN NICKEL BASE SUPERALLOYS
