Carbon/vinyl ester composites for enhanced performance in marine applications

The present study describes the processing and mechanical characterization of two different fibers (glass and carbon) and two different fabric architectures (woven roving and stitch bonded) made into composites with Dow Chemical's Derakane 510A-40, a brominated vinyl ester (VE) resin. Both E-glass and T700 carbon fibers are coated with VE compatible sizing. The composite panels are fabricated by the vacuum assisted resin transfer molding (VARTM), the specimens are machined, and the mechanical tests are conducted as per the accepted test standards. Tension, compression, in-plane shear, and interlaminar shear properties are measured and their associated failure modes are compared with each other. The specific properties of the composites are compared with that of the marine steel. The carbon composites have superior properties, higher specific strength, and specific modulus than the marine steel. The glass composites have higher specific strength but lower specific modulus than marine steel. The glass composites are well suited for constructing ship hulls which are only strength critical. The topside (upper) structures of the ship are stiffness critical. The carbon composites are applicable to both the topside and the hull structures of the ship to reduce the total weight. The straightness of the fiber and the FOE sizing are the possible reasons for the superior performance of the carbon composites. The predicted elastic constants based on the simple micromechanical equations of the composites agree very well with the experimental data.