A Crystal Plasticity Study of the Effect of the Initial Misorientation on Nanoindentation Response T. O. Fenercioğlu1,∗, M. Budnitzki1, J. Wang2, E. Günay3, T. Yalçinkaya3, R. Schwaiger2 S. Sandfeld1 1 Forschungszentrum Jülich Institute for Advanced Simulation, Julich, Nordrhein-Westfalen, Germany 2 Forschungszentrum Jülich Institute of Energy and Climate Research, Julich, Nordrhein-Westfalen, Germany 3 Department of Aerospace Engineering, Middle East Technical University, Ankara 06800, Türkiye ∗ o.fenercioglu@fz-juelich.de Keywords: Nanoindentation, Mechanics of Materials, Crystal Plasticity Finite Element Method The application areas of nanoindentation to quantify mechanical behavior of materials on different scales are expanding rapidly (see e.g. [1]). Examination of elasto-plastic behavior, anisotropy and time/rate dependent deformation characteristics for different temperatures with only a nano-scale indent on the sample surface offers significant potential for future developments. Nanoindentation also provides an opportunity to study size effects during the plastic deformation and the associated formation of defect structures. A comprehensive understanding of the effect of the testing setup and its imperfections on the measured data presents significant potential to improve the estimation of elastic and inelastic material properties from the experimental results. In this study, a systematic analysis for the effect of small initial misorientation between nanoindentation instrument and single crystal tungsten test sample is carried out using crystal plasticity finite element simulations. Crystal plasticity finite element analysis is widely used to investigate the deformation behavior of crystalline materials at mesoscale. Conventional and mechanism-based strain gradient crystal plasticity finite element analysis (CPFEA) are used to model plane strain wedge nanoindentation of single crystal tungsten. Numerical and experimental results are correlated to determine the misorientation axes and range between test samples and nanoindentation instrument. Results show that initial misorientation varies the lattice rotations and leads to their antisymmetric distribution under the indenter. References [1] Lucca, D.A., Herrmann, K., Klopfstein, M.J. (2010). Nanoindentation: Measuring methods and applications. CIRP Annals, 59, 803-819. 103
RkJQdWJsaXNoZXIy MjM0NDE=