Yu Seungmin, Cho Hyun-Jae, Ko Tae-Hoon, Kim Hak-Yong, Chung Yong-Sik, Kim Byoung-Suhk
Department of JBNU-KIST Industry-Academia Convergence Research, Jeonbuk National University, 567 Baekjedaero, Deokjin-gu, Jeonju-si 54896, Jeollabuk-do, Republic of Korea.
Department of Organic Materials and Textile Engineering, Jeonbuk National University, 567 Baekjedaero, Deokjin-gu, Jeonju-si 54896, Jeollabuk-do, Republic of Korea.
Nanomaterials (Basel). 2025 Aug 30;15(17):1335. doi: 10.3390/nano15171335.
This study investigates the effect of tensile strain during high-temperature carbonization on the microstructural development and mechanical properties of polyacrylonitrile (PAN)-based carbon fibers. The wet-spun stabilized PAN precursor fibers were carbonized at 1400 °C under various tensile draw ratios (0%, 5%, 10%, and 15%), followed by stress-free graphitization at 2400 °C in an argon atmosphere for 1 h to isolate the effects of the carbonization-stage tension. Structural characterization using XRD, 2D-XRD, Raman spectroscopy, and HR-TEM revealed that moderate tensile strain (5-10%) promoted significant improvements in crystallinity, orientation, and graphene layer alignment. Notably, the fiber drawn at 10% performed the best, with a reduced interlayer spacing (), increased lateral crystallite size (), high orientation factor, and minimal turbostratic disorder. These structural developments translated into the best mechanical properties, including a tensile strength of ~2.44 GPa, a Young's modulus of ~408.6 GPa, and the highest measured density (1.831 g/cm). In contrast, excessive strain (15%) induced microstructural defects and reduced performance, underscoring the detrimental effects of overstretching. The findings highlight the critical role of draw control during carbonization in optimizing the structure-property relationships of carbon fibers, offering valuable insight for the design of high-performance fiber processing strategies.
本研究调查了高温碳化过程中的拉伸应变对聚丙烯腈（PAN）基碳纤维微观结构演变和力学性能的影响。将湿法纺丝的稳定化PAN前驱体纤维在1400℃下以不同的拉伸倍率（0%、5%、10%和15%）进行碳化，随后在氩气气氛中于2400℃进行无应力石墨化1小时，以分离碳化阶段张力的影响。使用XRD、二维XRD、拉曼光谱和高分辨率透射电子显微镜进行的结构表征表明，适度的拉伸应变（5%-10%）显著促进了结晶度、取向和石墨烯层排列的改善。值得注意的是，以10%倍率拉伸的纤维表现最佳，其层间距减小、横向微晶尺寸增大、取向因子高且乱层无序最小。这些结构变化转化为最佳的力学性能，包括拉伸强度约为2.44 GPa、杨氏模量约为408.6 GPa以及测得的最高密度（1.831 g/cm³）。相比之下，过度应变（15%）会导致微观结构缺陷并降低性能，突出了过度拉伸的有害影响。研究结果强调了碳化过程中拉伸控制在优化碳纤维结构-性能关系方面的关键作用，为高性能纤维加工策略的设计提供了有价值的见解。
