蜂窝夹层复合材料的压缩损伤声发射特征

Acoustic Emission Characteristics of Compression Damage in Honeycomb Sandwich Composite

应用声发射技术对蜂窝夹层复合材料压缩损伤过程进行了试验研究。分析载荷与声发射信号关联图,依据其损伤过程和声发射特征,发现随着加载条件下载荷的增加,复合材料的损伤逐步增大。在加载初始阶段,仅有少量声发射信号,各种表征信号量小幅度增加;在加载中期,声发射信号增多,各种表征信号量不断增大;在加载后期,声发射信号有明显突增,各种表征信号量急剧增加。复合材料压缩损伤破坏与声发射的幅值、能量、撞击、上升时间、持续时间和计数等参量特征相关。根据各阶段特征参量滤波后所得信号分布与实际断裂位置相吻合。

Experimental studies on honeycomb sandwich composite compression damage process based on acoustic emission （AE） technique were carried out. By analyzing the load and acoustic emission signal correlation diagrams, on the basis of the damage process and acoustic emission characteristics, it was found that as load increases on the loading conditions, the composite material damage increases gradually. In the initial loading stage, only a few acoustic emission signals and kinds of AE characteristic parameters have some extent increase; in the middle of the loading, acoustic emission signals increase, and kinds of AE characteristic parameters also increase; in the later loading, acoustic signals have obvious paroxysmal increase, and kinds of AE characteristic parameters rapidly increase. It is also found that the acoustic emission characteristics such as amplitude, energy, hit, rise time, duration, count and other parameters in compression tests are useful for monitoring the damage development and failure of the specimen. The distribution of the signal which is filtered by the characteristic parameter of each stage conforms to the practical rupture position.