Hierarchical models for simulating the mechanical behavior of heterogeneous materials: an approach to high speed tool steel1

A hierarchical modeling strategy is presented which allows the computational simulation of the thermo-mechanical behavior of materials exhibiting different morphological characteristics at different length scales. As a typical example of such materials high speed tool steel is considered as some sort of in-situ metal matrix composite containing, at the micro level, carbidic inclusions in a martensitic steel matrix, and, at the meso level, clusters or stringers of inclusion rich areas. The macroscopic stiffness and strength behavior depends on the morphology at both levels which can be taken into account simultaneously by the proposed hierarchical concepts.