Modeling of Mechanical Tests on Composite Specimens Produced by 3D Printing

Abstract

ABSTRACT The thesis is focused on the modelling of mechanical tests on a composite specimen produced by 3D printing. The experimental, numerical and analytical techniques were utilized to compare the different composite specimens with different volumetric fractions of Carbon fiber filaments. The reinforcement by long fibers is provided to the ONYX matrix by layer-by-layer diffusion. This study contains the investigation of three separate specimen design i.e., - Rectangular specimen with longitudinal loading, transversal loading and the testing specimen with two contour lines of carbon fibers loaded in tensile, shear and combined modes. All these tests were performed under room temperature and uniaxial testing was done under strain-controlled loading. These tests are very useful to determine the reliability of the composite materials, especially produced by 3D printing. The numerical simulations were performed under consideration of reduced geometry with symmetrical consideration and with a suitable choice of finite elements. This study allows to predict the stiffness of elastic structure of the composite with carbon fibers. A proper filament orientation and density can be obtained by the proposed methodology.