Quantitative laser atom probe analyses of hydrogenation-disproportionated Nd–Fe–B powders

• Published in: Ultramicroscopy Vol. 111; no. 6; pp. 615 - 618
• Main Authors: Sepehri-Amin, H., Ohkubo, T., Nishiuchi, T., Hirosawa, S., Hono, K.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.05.2011
• Subjects: Atom probe; Atom probe analysis; Femtosecond; Ferrous alloys; Gallium; HDDR process; Hydrogen; Lasers; Magnetic materials; Nd–Fe–B magnets; Stoichiometry; Tomography; Hydrogen; Atom probe; Nd–Fe–B magnets; HDDR process
• ISSN: 0304-3991; 1879-2723
• DOI: 10.1016/j.ultramic.2010.11.015

We report a successful atom probe tomography of hydrides in hydrogenation-disproportionated Nd–Fe–B powder using a green femtosecond laser. The atom probe specimens were prepared from one particle of powder using the focused ion beam lift-out method. The atom probe tomography taken from an α-Fe/NdH 2 structure suggested that B and Ga (trace added element) were partitioned in the NdH 2 phase. The hydrogen concentration of 64 at% determined from the atom probe analysis was in excellent agreement with the stoichiometry of the NdH 2 phase. ► Atom probe tomography of hydrides in hydrogenation-disproportionated Nd–Fe–B powder. ► Successful quantitative analysis of hydrogen from NdH 2 lamellae. ► Direct observation of individual hydrogen atoms using laser assisted atom probe.