A Reference Hydride Ratio Method for the Resolution of Al/Fe Peak Overlapping in Atom Probe Tomography Experiments

Area of Science:

• Materials Science
• Analytical Chemistry
• Metallurgy

Background:

• Precise iron (Fe) concentration measurements are vital for understanding precipitation kinetics and mechanical property evolution in aluminum-iron (Al-Fe) alloys.
• The increasing use of recycled metals necessitates accurate impurity tracking in Al-alloys to assess their impact on microstructure and properties.
• Atom Probe Tomography (APT) offers precise composition measurements but faces challenges in peak identification and deconvolution, especially with molecular ions.

Purpose of the Study:

• To develop a method for improving the precision of Fe concentration measurements in Al-Fe alloys using APT.
• To address the complex peak overlapping issue in the mass spectra of Al-Fe systems.
• To provide a reliable approach for quantifying Fe in Al-alloys, particularly relevant for recycled materials.

Main Methods:

• Utilized Atom Probe Tomography (APT) for high-resolution compositional analysis.
• Developed a novel approach to solve overlapping peaks in the mass spectrum of Al-Fe alloys.
• Employed standard materials without Fe interference to determine the Al-hydride formation ratio.

Main Results:

• Successfully identified and deconvoluted overlapping peaks in the Fe isotope mass intervals within the Al-Fe system.
• Quantified the Al-hydride formation ratio from standard samples.
• Demonstrated a method to improve the accuracy of Fe concentration measurements in Al-Fe alloys.

Conclusions:

• The developed method effectively improves the precision of Fe concentration measurements in Al-Fe alloys by accurately resolving spectral interferences.
• This technique is essential for characterizing recycled Al-alloys and understanding the influence of Fe impurities.
• The approach offers a practical solution for complex peak overlapping challenges in APT analyses of multicomponent systems.