X-ray nanotomography and focused-ion-beam sectioning for quantitative three-dimensional analysis of nanocomposites.

Knowing the relationship between three-dimensional structure and properties is paramount for complete understanding of material behavior. In this work, the internal nanostructure of micrometer-size (∼10 µm) composite Ni/Al particles was analyzed using two different approaches. The first technique, synchrotron-based X-ray nanotomography, is a nondestructive method that can attain resolutions of tens of nanometers. The second is a destructive technique with sub-nanometer resolution utilizing scanning electron microscopy combined with an ion beam and `slice and view' analysis, where the sample is repeatedly milled and imaged. The obtained results suggest that both techniques allow for an accurate characterization of the larger-scale structures, while differences exist in the characterization of the smallest features. Using the Monte Carlo method, the effective resolution of the X-ray nanotomography technique was determined to be ∼48 nm, while focused-ion-beam sectioning with `slice and view' analysis was ∼5 nm.