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arXiv · 2409.14370

Machine Learning algorithms for optimization of magnetocaloric effect in all-d-metal Heusler alloys

Abstract

This study examines the application of machine learning algorithms, specifically the Random Forest regression model, to optimize the magnetocaloric effect in all-d-metal Heusler alloys. The model was trained using descriptors related to the mean properties of individual atoms, the properties of simple compounds in their ground state, and measures of chemical disorder. It demonstrated high accuracy in predicting structural properties, while exhibiting moderate accuracy in predicting magnetic properties. To identify optimal alloy compositions, a genetic algorithm was used to find those with the greatest differences in magnetization during martensitic transitions. Using this combined approach, the Ni-Co-Mn-Ti alloy system was thoroughly explored, resulting in the discovery of an alloy with a maximum magnetization difference. These results are consistent with previous research based on Density Functional Theory (DFT) and highlight the effectiveness of integrating machine learning with genetic algorithms for the discovery of new materials with outstanding magnetocaloric properties. The study emphasizes the need for further refinement of models capable of accurately predicting complex magnetic interactions, which is essential for fully leveraging the potential of all-d-metal Heusler alloys in practical applications.

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Danil Baigutlin, Vladimir Sokolovskiy, Vasiliy Buchelnikov, Sergey Taskaev. 2024-09-22. Machine Learning algorithms for optimization of magnetocaloric effect in all-d-metal Heusler alloys. https://arxiv.org/abs/2409.14370

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