变角度混杂复合材料层合板振动特性研究

Research on Vibration Characteristics of Variable Angle Hybrid Composite Laminated Plates

研究了由碳纤维(Carbon Fibre)和Kevlar纤维(Kevlar Fibre)制备的变角度混杂层合板的模态参数,以改善复合材料层合板振动特性。基于模态试验基本理论,采用模态力锤法获得了变角度混杂层合板的频响函数,拟合函数获得前三阶频率阻尼比。研究分析可知:变角度铺层作为芯层时,纤维角度变化对固有频率变化较平缓,均在0.9%左右。而变角度层作为面层时,纤维角度的变化可以有效提高层合板的固有频率,增加44.0%。刚度更高(与Kevlar纤维相比,杨氏模量是其2倍左右)的CF作为面层材而KF作为芯层时,固有频率增加,一阶固有频率最多提高62%,三阶固有频率最多提高57.1%。当铺层顺序为[±<60|75>/0k/90k]s整体振动特性最佳达到(基频为17.83Hz),相对于纯CF直线铺层提高了74.0%。

The modal parameters of variable angle hybrid laminates prepared from carbon fiber(CF(CARBON FIBRE))and Kevlar fiber(KF)were studied to improve the vibration characteristics.Based on the basic theory of modal testing,the frequency response function of the variable angle hybrid laminated plate was obtained using the modal force hammer method,and the damping ratios of the first three frequencies were obtained by fitting functions.According to experimental analysis,it has been found that when the variable angle layer is used as the core layer,the change in fiber angle The changes are relatively gentle,all around 0.9%.When variable angle layer is used as the surface layer,the change in fiber angle can effectively improve the natural frequency of the laminated plate,increase by 44.0%.When CF with higher stiffness(Compared to Kevlar fibers,the Young’s modulus is about twice that of Kevlar fibers)is used as the surface layer material and KF is used as the core layer,the natural frequency is higher.The natural frequency increases,with a maximum increase of 62%for the first order natural frequency and 57.1%for the third order natural frequency.When the laying sequence is[±<60|75>/0k/90k]s,the overall vibration characteristics are optimal(with a fundamental frequency of 17.83 Hz),which is 74.0%higher than pure CF linear laying.