The effect orientation of features in reconstructed atom probe data on the resolution and measured composition of T1 plates in an A2198 aluminium alloy

Maria A Mullin; Vicente J Araullo-Peters; Baptiste Gault; Julie M Cairney

doi:10.1016/j.ultramic.2015.04.005

The effect orientation of features in reconstructed atom probe data on the resolution and measured composition of T1 plates in an A2198 aluminium alloy

Ultramicroscopy. 2015 Dec:159 Pt 2:368-73. doi: 10.1016/j.ultramic.2015.04.005. Epub 2015 Apr 14.

Authors

Maria A Mullin¹, Vicente J Araullo-Peters¹, Baptiste Gault², Julie M Cairney¹

Affiliations

¹ School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, NSW 2006, Australia; Australian Centre for Microscopy and Microanalysis, The University of Sydney, Madsen Building F09, NSW 2006, Australia.
² Department of Materials, University of Oxford, Parks Road, OX13PH Oxford, UK.

PMID: 25896290
DOI: 10.1016/j.ultramic.2015.04.005

Abstract

Artefacts in atom probe tomography can impact the compositional analysis of microstructure in atom probe studies. To determine the integrity of information obtained, it is essential to understand how the positioning of features influences compositional analysis. By investigating the influence of feature orientation within atom probe data on measured composition in microstructural features within an AA2198 Al alloy, this study shows differences in the composition of T1 (Al2CuLi) plates that indicates imperfections in atom probe reconstructions. The data fits a model of an exponentially-modified Gaussian that scales with the difference in evaporation field between solutes and matrix. This information provides a guide for obtaining the most accurate information possible.

Keywords: Aluminium alloys; Atom probe tomography; Data analysis; Microscopy.