Effect of linear density and yarn structure on the mechanical properties of ramie fiber yarn reinforced composites

Effects of linear density and yarn structure on both static and dynamic mechanical properties of ramie fiber yarn reinforced composites (RYRCs) were investigated. The failure mechanisms of RYRCs were analyzed with the aid of ultrasonic C-scan and Scanning electronic microscopy (SEM). The results showed that the tensile strength of RYRCs increased gradually with increase of the linear density of the single yarns. The maximum tensile strength was obtained when the linear density reached 67.3 tex. However, a downtrend of the tensile strength was observed with further increase of the linear density of ramie single and plied yarns. The interlaminar fracture toughness was relatively high for RYRCs made from yarns with lower linear density due to the extensive fiber bridging observed during the double cantilever beam test. Meanwhile, the linear density and structure of ramie yarn had remarkable influence on the failure mode of RYRCs during the drop weight impact test.