中文摘要：

利用声发射技术对复合材料层合板的低速冲击过程进行动态监测。结合冲击载荷时间历程曲线,对声发射波形的振幅和持续时间所表征的材料内部冲击损伤演化规律进行分析。并综合声发射的能量、幅值和频率等特征参数的散点关系图,归纳了高能损伤点的分布规律,给出了不同损伤模式的参数特征。结果表明：复合材料层合板在冲击过程中的损伤演化可以分为基体裂纹迅速扩展、基体裂纹沿层间扩展并产生分层、大量纤维断裂导致最终破坏3个阶段,其对应的主要损伤模式分别为基体开裂、层间分层和纤维断裂;在低速冲击损伤过程中,基体开裂的声发射事件少,能量低;分层的声发射事件较少,能量高;纤维断裂的声发射事件多,能量较高。

英文摘要：

Acoustic emission （AE） technique was used to detect the process of composite laminates damage under low velocity impact. We use the impact load curve to analyze the damage evolution of composite laminates that is characterized by the amplitude and duration of AE waveform. The energy,amplitude and frequency of AE were analyzed together to conclude the distribution of peak points,and summarize the parameter of different damage modes. The result shows that the process of composite lamination damage is in three stages： （1） matrix cracks extend rapidly; （2） matrix cracks extend along interlayer and causes delamination; （3） large fibers break and lead to ultimate failure. The main damage modes of the three stages are matrix cracking,delamination,and fiber breakage. The characteristics of the three damage modes is： few AE events and low energy in matrix cracking; few AE events and high energy in delamination; more AE events and higher energy in fiber breakage.