An Efficient Method for Preparing High-Quality Atom Probe Tomography Samples of Dual-Phase Ti Alloys

Preparing atom probe tomography (APT) samples of dual-phase Ti alloys can be challenging. The existing focused ion beam (FIB) lift-out method is time-consuming and requires intensive experience in the process. Here, we combined electropolishing and FIB annular milling as a novel approach for the APT sample preparation of dual-phase Ti alloys. Electrochemical polishing is used to pre-sharpen the APT tip, while the FIB annular milling is used for fine polishing. This method reduces the preparation time by 40% compared to the existing site-specific FIB lift-out technique while maintaining similar background noise and mass resolution, as well as achieving a reduction in thermal tails in the mass spectrum. In this article, step-by-step procedures of this sample preparation method are described in detail, and the sample quality using this method is compared with that of samples prepared using the FIB lift-out method.