Effects of Hard Twisted Yarn on Mechanical Property in Fiber Structural Hybrid Composite Materials

Abstract

In this study, we have extended the concept of fiber hybrid and proposed fiber structural hybrid composite as the new concept. Fiber structural hybrid is defined as reinforcements consist from same kinds of fiber materials with different structure such as the fineness, the twisting state, and etc. In this study, the concept of the fiber structural hybrid was applied to the glass woven fabric composite and fiber structural hybrid composite materials with different twisting count and twisted structure were fabricated. By static tensile test and Finite Element Method (FEM) considering of the internal structure, the effects of the difference in twisting state of weft fiber on the initial fracture of fiber structural hybrid composites were investigated. In tensile test, it was clarified that tensile modulus and initial fracture stress were decreased by the increase in the twisted count and the number of doubling. In FEM, apparent interfacial strength inside of weft fiber bundle was decreased by the increase in twisting count and apparent interfacial strength was increased by the increase in number of doubling. From these results, initial fracture can be designed by applying the fiber structural hybrid concept to the composite materials, and the safer structural material can be realized.