M.Sc. Tezi Görüntüleme

      Cellular materials have many properties such as high strength/weight ratio, specific thermal properties, shock and vibration damping. For this reason, they are increasingly used in many industries such as aerospace, automotive, transportation and medicine. The aim of this thesis is to investigate the mechanical behavior of coated micro lattice structures and to develop finite element models including geometric defects of micro lattice structures. Mechanical properties of coated micro lattice structures were examined by compression tests and finite element method. Coating thickness, coating-strut adhesion interface and cell size effects were investigated numerically in a parametric manner. It was found that coating thickness and cell size had a significant effect on the strength and elasticity modulus values of the micro lattice structures. In addition, an important parameter that controls the mechanical properties of coated micro-lattice structures was found to be the damage behavior of the coating. Furthermore, micro struts were measured by scanning electron microscope to model geometric defects and unmelted or semi-molten powders adhered to the surface. As a result of the studies, it was seen that the unmelted powders on the struts affect maximum strain and geometric defects affect the strength value. The mechanical properties required for the application of the finite element method were obtained from nano-indentation tests using the inverse finite element method. In the context of the thesis, optimization methods, which were originally developed, were used for the inverse finite element method.