Compressive Strength of high Performance Fibers

Abstract

ABSTRACTSignificant research efforts have been carried out to improve the tensile modulus and tensile strength of high performance carbon and polymeric fibers. Experimental polymeric fibers (ordered polymer fibers) have been prepared with moduli >50 MPSI and tensile strength approaching one MPSI. However, the benefits of the above improvements in tensile properties for aerospace applications are limited because composites of these fibers have low axial compressive strength, which is a direct result of the poor axial fiber compressive strength. The poor axial fiber compressive strength has usually been attributed to the microfibrillar/fibrillar buckling. However, questions concerning the intrinsic limitations at the molecular level and the effects of intermolecular interactions are also considered important. Better understanding of these aspects will help in determining the theoretically achievable compressive strength and may aid in the development of higher compressive strength high performance fibers. These and other issues related to the compressive strength of high performance polymeric and carbon fibers are discussed in this paper.