development of braiding-pultrusion method and investigation of mechanical properties of composite rods produced by this method

in this research, a braiding-pultrusion production line is developed by modifying a conventional textile maypole braiding machine and adding it to a pultrusion line for production of braid-pultruded (bp) composite rods. in order to evaluate the mechanical properties of bp rods and study the effect of some braiding parameters, they were produced with different braid roving linear densities and braid angles. the results are also compared to those of unidirectional (ud) pultruded rods which were produced without braided fabric cover, but with the same fiber volume fraction and diameter.the results showed bp rods had higher shear modulus, but lower tensile modulus and flexural rigidity compared to ud rods. it was also concluded that increasing the braid roving linear density leads to an improvement in shear modulus, but a reduction in tensile modulus and flexural rigidity. moreover, the highest shear modulus is observed in the rod with braid angle of 45o. tensile modulus and flexural rigidity decrease when braid angle increases.