Production of natural fiber reinforced hybrid composites and investigation of mechanical properties

It is economically and ecologically very important to develop new composite materials that will not cause environmental problems after use by using natural fibers with high biodegradability instead of synthetic fibers with low biodegradability and to turn to the use renewable resources. The main purpose of this master's thesis is to better understand the mechanical properties of natural fiber reinforced composites, which are economically and ecologically important, and to expand their use. In this direction, composite materials using jute, flax and ramie natural fibers and hybrid composite materials in different variances of these fibers were produced by hand lay-up method. A total of 11 different productions were made and the densities and tensile and flexural strengths of the produced materials were examined. In addition, fracture surfaces formed as a result of mechanical tests were examined by scanning electron microscopy (SEM) and damage analyses were made. It was observed that the density values of the produced materials varied between 1.12 g/cm3 and 1.37 g/cm3. It was observed that the average tensile stress (52.4 MPa) and flexural stress (148.5 MPA) of ramie fiber reinforced composite were higher than flax fiber reinforced composite and jute fiber reinforced composite. Tensile and flexural stresses of jute/ramie hybrid composites were obtained between the tensile and flexural stresses of ramie fiber reinforced composite and jute fiber reinforced composite. However, the tensile and flexural stresses of the K9 (2K+2J+2K) sample, one of the jute/flax hybrid composites, were higher than the tensile and flexural stresses of the flax fiber reinforced composite and the jute fiber reinforced composite. When the SEM images of the fracture surfaces were examined, it was seen that the connection between the fibers and the polyester matrix was good, the rupture damage was mostly in the form of fiber breakage, and there were matrix cracks only in some small areas.