[Back]

M. Vogric, E. Povoden-Karadeniz:
"Multiscale homogenization of elastic properties in hypereutectoid steel";
Talk: Online Conference STEELSIM 2021, Wien; 2021-10-05 - 2021-10-07.

Hypereutectoid steels are of major importance for the railway and cable industry due to their good hardness and toughness. In-depth understanding of the link between their microstructure and mechanical properties presents therefore a significant industrial relevance. We have realized the multiscale modelling of macroscopic elastic properties of hypereutectoid steel based on the elastic properties of its constituent phases cementite and ferrite.

The presented model works through successive homogenization steps using the Eshelby matrix-inclusion approach and the definition of representative volume elements following quantitative microstructural criteria. Four different types of hypereutectoid steel microstructures are considered: lamellar or spheroidized globular pearlite, surrounded by a continuous or fragmented proeutectoid cementite film. Depending on the considered microstructure, various homogenization approaches are used at the different homogenization steps: 1) Mori-Tanaka approach, describing matrix-inclusion composites - spheroidized pearlite in this study, 2) Classical self-consistent scheme, describing polycrystalline aggregates - here lamellar pearlite or combination of pearlite and fragmented cementite, and 3) Generalized self-consistent scheme, describing aggregates of phases surrounded by matrix films - here used for pearlite surrounded by a continuous cementite film.

The influence of microstructural parameters such as the pearlite colony size or the thickness of the cementite film on Young´s and shear moduli and on the coefficients of the stiffness tensor is simulated, and the expansion of our multiscale approach to plasticity is considered. A proof of concept is obtained by comparing the calculated macroscopic elastic behavior of the material and experimental results from the literature.

hypereutectoid; steel; pearlite; cementite; ferrite; micromechanics; multiscale; homogenization

https://publik.tuwien.ac.at/files/publik_301554.pdf