Related Experiment Video
Updated: Mar 31, 2026

Processing of Bulk Nanocrystalline Metals at the US Army Research Laboratory
Published on: March 7, 2018
Effects of isoconcentration surface threshold values on the characteristics of needle-shaped precipitates in atom
Yasuhiro Aruga1, Masaya Kozuka2
1Materials Research Laboratory, Kobe Steel, Ltd., 1-5-5 Takatsukadai, Nishi-ku, Kobe 651-2271, Japan aruga.yasuhiro@kobelco.com.
Abstract:
Needle-shaped precipitates in an aged Al-0.62Mg-0.93Si (mass%) alloy were identified using a compositional threshold method, an isoconcentration surface, in atom probe tomography (APT). The influence of thresholds on the morphological and compositional characteristics of the precipitates was investigated. Utilizing optimum parameters for the concentration space, a reliable number density of the precipitates is obtained without dependence on the elemental concentration threshold in comparison with evaluation by transmission electron microscopy (TEM). It is suggested that careful selection of the concentration space in APT can lead to a reasonable average Mg/Si ratio for the precipitates. It was found that the maximum length and maximum diameter of the precipitates are affected by the elemental concentration threshold. Adjustment of the concentration threshold gives better agreement with the precipitate dimensions measured by TEM.
Related Concept Videos
Precipitate Formation and Particle Size Control
The obtained precipitate should be either a pure substance of known composition or easily converted to one by a simple process, such as ignition or drying. In addition, the precipitate should be insoluble and easily filterable. In general, filterability...
Precipitation Processes
Colloidal precipitates

