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Plain woven carbon fabric composites using different types of vinyl ester (VE) resin with different toughness have been prepared. The mechanical performances were characterized by different tests, such as tensile, tension-tension fatigue, thermoelastic stress analysis (TSA) and scanning electron microscope (SEM). The results showed that with increasing of fracture toughness of VE as well as adhesive strength between VE and carbon fiber (CF), the tensile strength improved by a range from 23.1 to 33.9%, and fatigue life of CF/VE composites increased by several times to several ten times when low toughness VE was used as control resin. The fatigue damage initiation of CF/VE composites has been investigated by thermoelastic stress analysis. It was found that the initiation and growth of fatigue damage such as matrix cracks was delayed, the linkage of matrix cracks in transverse bundles was inhibited with increasing of fracture toughness and interfacial shear strength (IFSS) of matrix resin.

Carbon fiber (CF) reinforced compositesusing different types of vinylester (VE)resin includingconventional VE resinhave been prepared. The mechanical performance were characterized by different tests, such as tensile, mode-I interlaminarfracture toughness, tension-tension fatigue and scanning electron microscope (SEM).The experimental results showed that the tensile strength of CF/VE composites changed at a wide range from 22.3% to 37.8% in comparison with the CF/conventional VE composite due to resin type, where the strain at failure was varying. The tensile strength increased with an increase of adhesive strength between carbon fiber and VE resin characterized by the microdroplet test. Namely, a good correlation between the tensile strength of composites and the adhesive strength was found. On the other hand, almost an inverse correlation was found between the tensile strength of composites and the interlaminar fracture toughness of composites obtained by DCB (double cantilever beams) tests. There was no apparent correlation found between the strain at failure for pure resins and the tensile strength of composites.Thefatigue life of CF/VE compositesincreased as well as the tensile strength with an increase of the adhesive strength between carbon fiber and the resin. The samples sometime survived 1000 times longer than that of CF/conventional VE compositewhen the maximum cycle stress was 70% of the tensile strength of the strongest composite.