Abstract:

Atom probe tomography (APT) is a microscopy and microanalysis technique that provides three-dimensional compositional mapping of materials with near-atomic resolution. APT complements more conventional techniques such as transmission electron microscopy, as APT can, in principle, detect light elements with the same efficiency as heavier elements, and as such can provide information on the distribution of hydrogen within a material. In this presentation, I will review briefly how atom probe works, and discuss the recent developments in the technique, with an emphasis on cryogenic preparation and specimen transfer protocols that are enabling analysis of hydrogen at the near-atomic scale in a range of engineering alloys.