弱粘接结构中谐振频率特性

为了研究弱粘接结构界面波动特性,利用弹簧模型方法研究了水-铝-粘接剂-铝-水多层结构中的波动特性,并利用界面刚度系数的变化研究了反射系数与谐振频率之间的变化关系以及谐振频率的漂移规律,通过粘接层厚度的变化研究了谐振频率阶数的变化规律.理论分析和数值计算结果表明:粘接层厚度较薄时,弱粘接结构的谐振频率出现双峰现象;粘接层厚度较厚时,弱粘接结构的谐振频率将会出现多峰现象,且随着粘接层厚度的增加,粘接结构将会出现多阶谐振频率。

Resonance Frequency Characteristics in Weak Bonded Structures

A spring model method is established for researching wave characteristics of the weak bonded structure,which is used to change the resonance frequency and reflection coefficient.According to the relationship between the ultrasonic propagation characteristics and stress-strain condition,the reflection coefficient of the bonding layer with zero thickness is derived.The reflection of wave for equal-thickness aluminum plates under the thickness of the bonding layer is calculated.Analysis and computation show that resonance frequency curves can engender on the shift of "the shift right peaks" with the effect of the variety of the interface stiffness.The influences on the multi-mode resonance frequency of a layered structure with the thickness of the adhesive layer are calculated,and the influence of the "multi-peak" of resonance frequency curves is discussed.