Effect of Fiber Thickness on Critical Fiber Ratio in Mechanical Tests of Nettle-Polymethylmethacrylate Composites

The aim of this study was to determine the critical ratios of fiber (vfcrit.) In nettle fiber/polymethyl methacrylate composites depending on fiber thickness. Polymethyl methacrylate, a brittle matrix, was used for this purpose. Nettle fiber, produced by natural method, was used in the production of polymethylmethacrylate composites with nettle fiber fiber with a ratio of 1,25%, 2,5, 3,75 and 5% by Hand lay-up.The tensile strength, bending strength, and impact strength of these compenents were used to obtain critical fiber ratios based on the thickness of the fiber. The physical properties of the fiber and its interaction with the matrix were determined by XRD and FITIR tests, respectively. SEM images were examined with the help of the observed microstructure of the fracture surfaces. According to the obtained data, critical fiber diameter values in thick fibers are higher than thin fibers. The results of the study showed that fine fibers had a positive effect on the mechanical properties of the materials compared to thick fibers？