Compression properties for square braided fabric without constraint to the side face

Cyclic compression test was performed on square braided fabric and the hysteresis loop in load and displacement was investigated. The observation of the cross section with optical microscopy was performed and the mechanism of deformation under compressive loading was clarified. Inside structure of braided fabric and compressive properties were extremely changed at first compression and then tended to converge to stable structure; compression ratio, reconstruction ratio and elastic modulus kept almost constant value after 2nd cycle. The change in structure of braided fabric was resulted from increase in crimp ratio of fiber bundle V and change in braiding angle.