Parameter free quantitative analysis of atom probe data by correlation functions: Application to the precipitation in Al-Zn-Mg-Cu

TL;DR

This paper introduces a parameter-free method for analyzing atom probe tomography data using correlation functions, enabling detailed characterization of precipitates in alloys without prior assumptions.

Contribution

It adapts small-angle scattering analysis techniques to atom probe data, providing a novel, efficient approach for quantifying microstructural features.

Findings

Effective extraction of particle size, composition, and distribution.

Application to Al-Zn-Mg-Cu alloy demonstrates method's utility.

Improved understanding of precipitation mechanisms.

Abstract

Atom probe tomography enables precise quantification of the composition of second phase particles from their early stages, leading to improved understanding of the thermodynamic and kinetic mechanisms of phase formation and quantify structure-property relationships. Here we demonstrate how approaches developed for small-angle scattering can be adapted to atom probe tomography. By exploiting nearest-neighbor distributions and radial distribution function, we introduce a parameter free methodology to efficiently extract information such as particle size, composition, volume fraction, number density and inter-particle distance. We demonstrate the strength of this approach in the analysis of a precipitation-hardened model Al-Zn-Mg-Cu high-strength lightweight alloy.