Abstract Aramid fiber (AF) reinforced by polyamide (PA) composites are excepted to have good interfacial matching due to their similar chemical interactions of hydrogen bonding. Thus, polarizing optical microscope (POM), transverse fiber bundle (TFB) test, and droplet micro-debonding technique were respectively performed to characterize interfacial crystallization, adhesion and shear behaviors of AF/PA6 composites with different thermal treatments. Both interface adhesion and AF fibrillation are enhanced with decreasing cooling rate or increasing annealing temperature due to the increased interfacial transcrystallization interaction. However, fast cooled interface also presents a high interfacial shear strength (IFSS) due to favorable normal residual stress. The apparent IFSS is believed to be a result of competition between crystallization enhancing interfacial interaction, interfacial mismatching aggravating debonding, and an uncertain residual stress positive or negative for load transfer. TFB failure mechanism including AF fibrillation and kinking are schematically presented. Fibrillation strength of AF is found to follow Weibull distribution evaluated by droplet micro-debonding technique.

中文翻译：

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不同热处理条件下芳纶纤维/聚酰胺6复合材料的界面粘附和剪切行为

摘要 聚酰胺（PA）复合材料增强的芳纶纤维（AF）由于具有相似的氢键化学相互作用而具有良好的界面匹配。因此，分别进行偏光显微镜（POM）、横向纤维束（TFB）测试和液滴微剥离技术来表征不同热处理的AF/PA6复合材料的界面结晶、粘附和剪切行为。由于界面晶化相互作用的增加，界面粘附和 AF 原纤化都随着冷却速率的降低或退火温度的升高而增强。然而，由于有利的法向残余应力，快速冷却界面也呈现出高界面剪切强度（IFSS）。明显的 IFSS 被认为是结晶增强界面相互作用、界面失配加剧脱粘和不确定残余应力对载荷传递的正负值之间竞争的结果。包括 AF 颤动和扭结在内的 TFB 失效机制被示意性地呈现。发现 AF 的原纤化强度遵循通过微滴微剥离技术评估的威布尔分布。