Big volume 3 dimensional printer design and investigation of production parameters of abs polymer matrix carbon fiber reinforced composites by fused deposition modeling

The aim of this study was manufacturing of a modular additive manufacturing system with a large build volume, which allows parameter changes to be made based on fused deposition modeling, investigation of the effects of different process parameters on mechanical properties of thermoplastic and polymer matrix composite materials, determination of the ideal process parameters according to the system and investigation of the fabricability of topology optimized parts in fused deposition modeling. With this aim firstly, the design and manufacture of a three dimensional printer with a build volume of 1000x1000x1000 mm, in which large sized parts can be produced with high dimensional accuracy, was realized. In the production of thermoplastic materials and carbon fiber reinforced ABS composites, five different process parameters and three different levels for each parameter were determined and test samples were produced for tensile testing. In the production of test specimens, three different build angles (30 /-60°, 45 /-45°, 90/0°), three different infill density (20%, 60%, 100%), three different print speeds (20, 40, 60 mm/s), three different nozzle temperatures (235, 255, 265 °C) and three different table temperatures (70, 95, 110 °C) were used and optimum process parameters were identified according to the mechanical values obtained by Taguchi experimental design. Consequently, best mechanical properties were obtained at 100% infill density, 30/-60° build angle, 20 mm/s print speed, 255 °C nozzle temperature and 110 °C table temperature. The effects of different process parameters on the internal structure of the parts were evaluated by scanning electron microscopy images from the fracture surfaces. It was seen that carbon fiber reinforced composite samples had a large amount of pores. It was also found that from the micrographs the adhesion between the fiber and matris was insufficient, which led to fiber pull out from the matrix material. It was observed that the process parameters significantly affect the layer structure of the parts, mechanical properties and material behaviors. In the samples produced from carbon fiber reinforced composite materials, the tensile strength decreased by 12% compared while the modulus of elasticity increased by 70%.compared to the non-reinforced samples. As a result of topology optimization under the boundary conditions determined on a wing rib by using process parameters and mechanical values, the mass decreased from 0.71 kg to 0.36 kg and the mass reduced by 48.12%. Topology optimized wing rib was fabricated by big build volume additive manufacturing system with using carbon fiber reinforced composite materials.