Uniaxial Compressive Strength of High Modulus Fibers for Composites

Abstract

Axial compressive behavior of carbon and high modulus organic fibers (such as Kevlar and PBT) has been discussed. The compressive strength of carbon fibers is found to in crease with a decrease in density, over a limited density range. Possible models for low and high compressive strength carbon fibers are proposed which are able to explain the unusually high compressive strength for the lower density fiber. Complementary wide and small angle x-ray scattering data is presented which supports the above models.