Polycrystalline plasticity modeling of anisotropic grain structures and statistical size effect in metallic alloys

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2022-6-14

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Orhun, Bulut

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In this thesis, two important microstructural phenomena affecting the plastic behavior of metallic materials are addressed through a local crystal plasticity modeling framework. Initially the influence of anisotropic grain structure developing during various forming procedures and additive manufacturing processes is studied following a multiscale modeling strategy, where Representative Volume Elements (RVEs) are analyzed under axial loading conditions. Macroscopic response of different degrees of anisotropic microstructures and related lattice alignment effects are discussed in detail. Then, the influence of specimen thickness to grain size ratio affecting the forming behavior of micron sized specimens is studied. The statistical size effect that can be captured through a local crystal plasticity model is discussed in comparison to the existing literature. The thesis is concluded with an outlook for possible future studies.

Subject Keywords

Crystal plasticity, Additive manufacturing, Anisotropic microstructure, Texture, Statistical size effect

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https://hdl.handle.net/11511/98135

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

B. Orhun, “Polycrystalline plasticity modeling of anisotropic grain structures and statistical size effect in metallic alloys,” M.S. - Master of Science, Middle East Technical University, 2022.