Interfacial Modification of Macro Fiber Composites for Active Low-Frequency Vibration Suppression

Low-frequency vibration of thin-walled materials, which are widely used in aircraft, can lead to fatal damage of aircraft components and even serious accidents. Although active vibration suppression using macro fiber composite (MFC) holds promise, the weak internal interfaces of MFC-specifically, those among the piezoelectric ceramics, the polymer matrix, and the interdigitated electrodes-seriously restrict the actuation strain and effective suppression bandwidth, limiting its engineering application under broadband aerodynamic excitation. In this work, an MFC-based self-feedback device integrating sensor and actuator is proposed. To address this, the performance bottleneck of the MFC actuator is overcome through a combined interface modification strategy combining plasma etching and dopamine-inspired modification. The interfacial modification elevates the maximum actuation strain of the MFC from 915 με to 1105 με (an increase of 20.8%). When applied to an aluminum cantilever beam, a vibration suppression ratio of 98.11% is achieved at the resonant frequency (75 Hz), and the effective suppression bandwidth (suppression ratio > 50%) reaches 77 Hz. Notably, this strategy is effective on aluminum, stainless steel, and carbon fiber substrates, as equally efficient broadband suppression is realized on all three materials. A powerful pathway is thus provided to unlock the full potential of MFC for low-frequency, broadband active vibration control in aerospace applications.