3D Atomic Characterization by Using Field Ion Computed Tomography

Summary form only given. Three dimensional field ion microscopy (FIM) images have been reconstructed using successive images of a FIM movie. This capability opens a new dimension to the observation with the FIM of various crystallographic features. The resolution of the instrument is proven to be better than 0.05 nm in depth and 0.3 nm laterally in favourable cases. This enables small objects to be observed 3D. For instance, for the first time, "Guinier-Preston" zones were imaged in 3D in steel. Using this technique, the volume fraction of precipitates in an AlZrSc alloy was directly measured in large volume compared to 3DAP dataset. The shell like structure of these precipitates was also clearly imaged. Others examples will be presented