We studied on automation of segmentation using deep learning, which has been remarkably developed in recent years.For the microstructural image of ferrite-martensite dual phase steel, we tried to segment the ferrite phase, martensite phase, and ferrite grain boundary in different colors individually. We created two models, SegNet and U-Net that can perform segmentation with high accuracy and compared the accuracy with an existing method.As a result, we demonstrated that models using deep leaning is more accurate than the existing method. In particular, U-Net model shows highly accuracy of segmentation for material microstructures.

Materials informatics seeks to establish microstructure–property linkage hidden in materials. A topological analysis of persistent homology and machine learning are combined to model microstructure–property linkage for dual‐phase steels, where a descriptor of persistent images is employed to characterize the microstructure and stress–strain curves are predicted using an artificial neural network. The correlations between stress and microstructure descriptor of persistent images are estimated using sensitivity analysis, Bayesian information criterion, and the least absolute shrinkage and selection operator (LASSO), respectively. The three methods identify consistent correlations, indicating that persistent images are capable of interpreting properties. Furthermore, the established artificial neural network model exhibits good accuracy and satisfactory property prediction performance. The proposed approach is expected to provide a new avenue for materials informatics and thus promote materials research.