Elastic analysis of tensile behavior of a composite using unidirectionally aligned staple-spun yarn preform

Abstract

Staple-spun yarn has been attracting attention as a fiber assemblage for composite fabrication for a decade. Using spun yarn as a fiber assemblage allows us to obtain a higher volume fraction with better fiber alignment if discontinuous fibers are used as reinforcement. However, a staple-spun yarn structure has a very complex geometry of fiber arrangement (such as twist and migration) as well as fiber discontinuity. These complexities make it difficult to analyze a composite system using staple-spun yarn as a fiber assemblage. In this study, a mathematical formulation was developed for the elastic solution of the tensile behavior of a composite system using unidirectionally aligned staple-spun yarn as a fiber assemblage. The influence of the twist angle on the effective axial modulus of the composite and the stress and strain distributions are discussed using the proposed approach.