Correlation analysis of materials properties by machine learning: illustrated with stacking fault energy from...

Advances in machine learning (ML), especially in the cooperation between ML predictions, density functional theory (DFT) based first-principles calculations, and experimental verification are emerging as a key part of a new paradigm to understand fundamentals, verify, analyze, and predict data, and design and discover materials. Taking stacking fault energy (γ_SFE) as an example, we perform a correlation analysis ofγ_SFEin dilute Al-, Ni-, and Pt-based alloys by descriptors and ML algorithms. Theseγ_SFEvalues were predicted by DFT-based alias shear deformation approach, and up to 49 elemental descriptors and 21 regression algorithms were examined. The present work indicates that (i) the variation ofγ_SFEaffected by alloying elements can be quantified through 14 elemental attributes based on their statistical significances to decrease the mean absolute error (MAE) in ML predictions, and in particular, the number of p valence electrons, a descriptor second only to the covalent radius in importance to model performance, is unexpected; (ii) the alloys with elements close to Ni and Co in the periodic table possess higherγ_SFEvalues; (iii) the top four outliers of DFT predictions ofγ_SFEare for the alloys of Al₂₃La, Pt₂₃Au, Ni₂₃Co, and Al₂₃Be based on the analyses of statistical differences between DFT and ML predictions; and (iv) the best ML model to predictγ_SFEis produced by Gaussian process regression with an average MAE < 8 mJ m^-2. Beyond detailed analysis of the Al-, Ni-, and Pt-based alloys, we also predict theγ_SFEvalues using the present ML models in other fcc-based dilute alloys (i.e., Cu, Ag, Au, Rh, Pd, and Ir) with the expected MAE < 17 mJ m^-2and observe similar effects of alloying elements onγ_SFEas those in Pt₂₃X or Ni₂₃X.