复合材料试验件缺陷在载荷的作用下均有可能扩展而成为声发射源, 对这些缺陷在试验件受载过程中的区分及定位日益成为声发射信号数据分析的主要方面。对复合材料试验件外载荷试验中声发射信号的特征进行简要分析, 对大幅值长时间的信号及大幅值短时间的信号能量分布及通道分布进行了试验分析。结果表明, 声发射信号可以较准确反映试验件受外载荷过程中的变化及损伤区域, 能粗略区分损伤类型, 但定位精度有待进一步提高。进一步验证了, 幅值大发射时间长的信号可表示试验件的宏观分层损伤, 而幅值大发射时间短的信号可表示试验件产生的纤维断裂损伤, 并可表示损伤区域发生的变化。

Defect in composite specimens can possibly be extended while under loading and becomes the acoustic emission source. Distinguishing and locating these defects in the load test piece are increasingly becoming the main aspects of acoustic emission signal data analysis. Characteristics of acoustic emission signal of the composite test piece under loading are analyzed briefly. Special attention is paid to the signal of large amplitude both with longer and shorter transmitting time periods, and their energy and channel distributions are analyzed. The results show that acoustic emission signal can accurately reflect the changes in the process of test load and damage area and can roughly distinguish types of damages, but the positioning accuracy needs to be improved. It is further validated that signals of large amplitude with longer transmitting time can be expressed as test piece extrusion generated by the macro delamination, whereas signals of large amplitude with short shooting time might be related with the fiber fracture damage when the said test parts being under tensile stress.[1]郑洁, 姚磊江, 程起有, 等.复合材料损伤的声发射试验研究[J].机械科学与技术, 2010, 29(11):1478-1481.[2]刘怀喜, 张恒, 闫耀臣.玻璃纤维/环氧树脂复合材料损伤与断裂过程的声发射特性[J].材料与表面处理, 2004(3):43-44.[3]李海斌, 阳建红, 刘承武, 等.复合材料随机渐进失效分析与声发射监测[J].复合材料学报, 2011, 28(1): 223-229.