Effect of long fibers angle on transverse strength in polyester pultruded rod

In Pultrusion process unidirectional long fibers (UD) has the most application as a reinforcer element due to high reinforcing level. But pultrusion process only can use this type of fibers on the longitudinal direction. Therefore the products of this process having high modulus and strength in the longitudinal direction but have low level of modulus and strength in the transverse direction. Other shape of reinforcer also have some process limitations such as complexity of utilizing them on process and lower level of reinforcing in compare with UD. Due to these infirmities, application of pultrusion products on special cases that profiles stands under transverse loads, encountered applied limitations. By preparing pultruded rod (E-glass / polyester) samples with different fiber angles and testing them with three point flexural test, observed with UD fiber angle increase toward pultruded rod direction, finally modulus and strength on transverse direction were increased