热处理对碳纤维/聚酰胺6复合材料界面结晶及力学性能的影响

探究了热处理对聚酰胺6（PA6）在碳纤维（CF）表面的结晶行为及其界面力学性能的影响。利用差示扫描量热法（DSC）、偏光显微镜（POM）观察法等分析手段考察了热处理对PA6在CF表面结晶行为的影响，揭示了在热处理过程中，PA6进行链段重排，形成小且不完善的新结晶，导致结晶度的上升以及界面横晶形貌的完善；进一步通过单丝微球脱粘实验和单向CF/PA6复合材料横向拉伸实验考察了热处理对PA6与CF的界面结合性能的影响，揭示了经退火热处理的试样由于弱界面和应力集中的减少使界面剪切强度增加且单位体积断裂能下降。

Effects of heat treatments on the interfacial crystallization and mechanical properties of carbon fiber/polyamide 6 composites

The effects of heat treatments on the crystallization behavior of polyamide 6 (PA6) on the surface of carbon fiber (CF) and their interfacial properties were explored. The effects of heat treatments on the crystallization behavior of PA6 on the surface of CF were characterized by differential scanning calorimetry (DSC) and polarizing microscope (POM) observation. The results show that the PA6 segments are rearranged during the heat treatment to form small and imperfect new crystals, which leads to the increase of crystallinity and the improvement of interfacial transcrystallization morphology. The interfacial property of CF/PA6 composites was characterized by micro-debonding test and unidirectional CF/PA6 composites transverse tensile test. It is revealed that the decrease of the weak interface and the stress concentration lead to the increase of the interfacial shear strength and the decrease of the fracture energy per unit volume of the annealed samples of CF/PA6 composites.