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

Wei Liu,Fujun Xu,Xiaoyun Liu,Yang Gao,Yiping Qiu

doi:10.1177/1558925019835164

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.

Highlights

Composites applied in aerospace industry are required to have excellent mechanical properties, including high tensile, bending, and compressing strengths
All the fiber had a deteriorative surface at both temperature-program-controlled method (TPCM) and quenching method (QM) cooling rates
For dry-jet wet-spun carbon fiber, TPCM and QM treatments induced some grooves along its longitudinal direction

Summary

Introduction

Composites applied in aerospace industry are required to have excellent mechanical properties, including high tensile, bending, and compressing strengths. The dry-jet wet-spun and wet-spun PAN carbon fibers were cryogenically treated in different cooling rates. Evenly distributed micro-cracks were observed on both QM-treated dry-jet wet-spun and wetspun carbon fibers, which indicated that the surface of carbon fiber can be damaged by the cryogenic quenching process.

Results

Conclusion