Identify Survived Key Features and Relevant Mechanisms for Designing High-Entropy Carbides via AI or Machine Learning

Multielement high-entropy carbides (HECs) provide many opportunities for HECs to obtain optimal combinations of various properties, e.g., high strength and high flexibility, leading to high toughness. However, the multielements significantly increase the compositional arrangements, challenging the development of advanced HECs. Machine learning (ML) provides a powerful approach to HEC design/discovery. Identifying key parameters or selecting the key features is crucial for carbide design with desirable properties. In the meantime, developing a reliable ML model with minimized mutual interference from multiple features, toward more accurate property predictions, also benefits the carbide discovery. In this study, we use a small carbide database to study the correlations between elastic moduli and 13 features with the assistance of recursive feature elimination (RFE) and investigate how the feature selection affects the prediction of HECs' properties. It is demonstrated that the mutual interference among highly correlated features may have a negative influence on the accuracy of ML prediction due to their mutual interference or redundant noise. For HECs, a few basic features are identified, which largely determine their elastic moduli. Among them, electron work function and valence electron concentration (VEC) appear to be more responsible for bulk and shear/Young's moduli, respectively. Other parameters are crucial for all elastic moduli, such as mixing entropy, formation energy, bond order, and bond length. This study demonstrates the significance of identifying the prominent features with lowered mutual interference or noise in further HECs with optimal properties.