Multi-Scale Framework-Based Crystal Plasticity Modeling and Texture Evolution of Deformation Behavior of Aisi 304 Stainless Steel Micro-Tubes Manufactured Through 3d-Fbf Technology

Abstract

The grain size often influences the precision and the quality of products manufactured via micro-forming at the micro-scale. Macro-scale finite element modeling (FEM) cannot accurately predict the nonuniform deformation and microstructural evolution at the micro-scale. Besides, the micro-scale FEM is challenging for forming processes with complex loading boundary conditions. Thus, in this study, a multi-scale framework-based CPFEM is proposed to study the deformation behavior of micro-tubes manufactured through the 3D-FBF process. The acquired results show that significant nonuniform deformation is caused by greater geometric dimensions and smaller grain sizes, which increase the bending radius of micro-tubes at the macro-level. Besides, a larger offset leads to higher flow stress, larger lattice rotation angles, and consequently, a larger bending radius for the micro-tube, and grain orientation also influences bending deformation, with easily deformable grain orientations leading to greater stress distribution within the grains.

Keywords: Micro-forming, crystal plasticity, multi-scale modeling, 3D-free bending forming (3D-FBF), Size effect