风电叶片复合材料在三点弯曲过程中的声发射研究

为研究风电叶片复合材料损伤破坏的声发射特性以及复合材料的力学性能,对含有纤维预断试件和无纤维预断的完好试件分别进行了三点弯曲力学性能试验,并在加载过程中采用声发射检测仪实时监测整个损伤破坏过程。对采集到的声发射信号处理分析,便可获得风电叶片复合材料的弯曲力学性能和损伤破坏的声发射特性。试验结果表明:玻璃纤维复合材料在弯曲载荷作用下出现典型的破坏特征包括纤维断裂、纤维/基体脱胶和纤维分层。纤维预断试件的声发射信号波形最高幅度达到2.5 V,频带分布在20~300 k Hz范围;无纤维预断试件的声发射信号波形最高幅度为0.07 V,频带分布在10~180 k Hz之间。

Acoustic Emission Research of Wind-power Blades Composites in Three Point Bending Test

In order to study the characteristics of acoustic emission (AE) signals of wind-power blades composites in the process of damage,as well as the mechanical properties of composite materials. The fiber fracture specimens and intact specimens were respectively used to do the three point bending test. The acoustic emission instrument was applied to do real-time detection during the whole loading and damage process. By analyzing the collected AE signals,the mechanical properties of composites and the AE signal characteristics could be obtained. The experimental results show that typical damage feature of glass fiber composites under the bending load include fiber breakage,fiber/substrate debonding and fiber delamination. The highest amplitude of signal waveform of fiber fracture specimens is 2.5 V and the frenquency band is 20-300 kHz while the highest amplitude and frenquency band of specimens without fiber fracture is 0.07 V and 10-180 kHz respectively.