Tensile and interfacial properties of dry-jet wet-spun and wet-spun polyacrylonitrile-based carbon fibers at cryogenic condition

Abstract

For carbon fiber–reinforced polymer composites applied in aerospace industry, the mechanical performance of carbon fiber in extreme temperature environment is of great importance. In this study, carbon fiber produced by dry-jet wet spinning and wet spinning approaches were cryogenically conditioned at different cooling rates. After cryogenically conditioned at sharp cooling rate, both fibers have around 10% decreases in tensile strength due to the huge hoop stress induced by the quenching process. However, after cryogenically conditioned at slow cooling rate, the interfacial shear strength between the two kinds of carbon fibers and epoxy resin was significantly enhanced. Furthermore, scanning electron microscopy, atomic force microscopy, and the Raman spectroscopy were conducted to detect the micro-structures and surface morphologies of the cryogenically conditioned carbon fibers. This study provided fundamental data for the material design and application of the carbon fiber at extreme temperature environments such as aerospace or other industrial fields.