碳纤维中的单层石墨物相及其对力学性能的影响

Effect of Monolayer Graphite Phase in Carbon Fiber on the Mechanical Property

依据碳纤维中各种物相的X射线衍射特性,确认PAN基碳纤维中除了乱层石墨微晶外,还存在大量的单层六元环C原子层面物相,建立起两种非完整结晶物相的定量分析方法.实验结果表明,随着退火温度由1350℃上升到2400℃,Tx-3高强型碳纤维中的单层石墨含量由59.6%下降到34.8%,乱层石墨含量由40.4%上升为65.2%.与此同时,碳纤维的拉伸强度则由3.65GPa下降到2.05GPa,而延伸率也由1.04%下降到0.58%.并对PAN基碳纤维中单层石墨对其力学性能的影响也进行了初步的探讨.

According to the character of the X-ray diffraction patterns of different phases in PAN carbon fiber, it can be affirmed that there still exist plentiful monolayer graphite with six-membered ring, besides muhilayer graphite. We also found two kinds of quantative methods for analyzing crystaline phase with defaults, which can be used to study the effect of monolayer graphite in carbon fiber upon its mechanical property.