Abstract
The effect of surface treatment on the mechanical properties of unidirectional composites using glass/nylon 6 commingled yarn was studied with three kinds of surface treatment. Commingled yarn composites of unidrectional alignment were fabricated by compression with heating in mold. Three-point bending tests were carried out in both longitudinal and transverse directions. Bending properties were discussed in relation to acoustic emission (AE) properties. The fracture surfaces of test pieces in transverse direction were observed by scanning electron microscopy (SEM) to examine the adhesion between fiber and matrix. Longitudinal bending properties were not affected by the kind of surface treatment. The fracture mechanisms, however, were quite different as revealed by AE properties. In the case of transverse bending test, the bending strength was strongly affected by the surface treatment. SEM observation of the fracture surfaces showed that the surface treatment appreciably changed the adhesion between fiber and matrix.
