金属基复合结构粘接强度的非线性超声混频检测

采用非线性超声混频方法对金属基复合结构的粘接强度进行表征研究。以不同固化剂含量的铝合金丙烯酸酯粘接结构作为检测对象,基于非线性超声混频的共振条件及其作用机制,并结合粘接固化机理,开展了非线性超声混频实验。非线性超声混频模式选取两列横波生成和频纵波的方式,实验测量并计算不同基频周期数下的超声非线性参量。通过拉伸实验标定粘接结构的粘接强度,并采用扫描电镜分析拉伸断面微观结构,进而分析超声非线性参量与粘接强度的关系。从实验结果可以看出在不同周期的基频信号激励下,超声非线性参量随着粘接强度的增大均呈现出减小的趋势。研究表明非线性超声混频信号对金属基复合结构粘接强度的变化比较敏感,可以适用于类似结构件粘接强度状态弱化的表征。

Detection of bonding strength of metal matrix composite structure using nonlinear ultrasonic mixing method

The nonlinear ultrasonic mixing method was used to detect the bonding strength of metal matrix composite structure. Based on the resonance conditions and the curing mechanism, experiments were conducted for detecting the aluminum alloy-acrylate bonding structures with different curing agent content. A pair of shear waves was chose as the primary waves to measure the nonlinear mixing parameters under different fundamental cycle. In order to analyze the relationship between bonding strength and nonlinear mixing parameters, the bonding strength of specimens were calibrated by tensile test, and tensile sections of specimens were investigated by SEM. The results demonstrated that nonlinear parameters decrease with the increase of bonding strength under different fundamental cycle. It shows that the nonlinear ultrasonic mixing method is sensitive to bonding strength of the metal matrix composite structure. Therefore, the nonlinear ultrasonic mixing method can be applied to characterize the deterioration of bonding strength of similar structure.