Abstract
We developed an approach to analyze local thermal stresses in hypereutectic high-chromium cast irons using image-based finite element modeling (FEM) based on real metallographic images. Model preparation included Otsu thresholding of the microstructure, filtering noise objects, and directly assigning the spatial phase distribution from the binarized image without intermediate geometry construction in computer-aided design (CAD) systems. To verify the proposed approach, Drawing Exchange Format (DXF)-based and image-based FEM models constructed from the same microstructural data were compared, and the influence of finite element size on the calculated stress state was investigated. The results showed that, with a progressive reduction in finite element size, the image-based simulation results approached those obtained using the DXF-based models despite the discrete pixel-based representation of the phase boundaries. The image-based approach reproduces the main features of the local stress distributions obtained using the DXF-based models while eliminating the need for image vectorization and intermediate CAD/DXF geometry construction, thereby substantially simplifying the preparation of computational models of real microstructures. The obtained results confirm the applicability of image-based FEM for comparative analysis of local thermal stress distributions in complex multiphase microstructures of high-chromium cast irons.