Damage Characterization of Carbon Fiber Composite Pressure Vessels Based on Modal Acoustic Emission

This study characterized the damage characteristics of carbon fiber composite pressure vessels by the modal acoustic emission (MAE) method. The study showed how to use the extracted damage modal features and established MAE parameters to determine the damage mode of composite pressure vessels. First, the A₀ and S₀ Lamb modes of the AE signal were split through mode separation, and the time window was selected to establish the MAE characteristic parameters. Subsequently, based on the MAE parameters and the damage mode characteristics established from single damage experiments, a damage mode discrimination method was established. A bending test of carbon fiber composite laminates proved that the modal separation method and the MAE parameters establishment are reasonable and effective. The results from the hydraulic test of the graded loading performed on 20 MPa carbon fiber composite pressure vessels showed the accuracy of the damage mode discrimination method, and the damage state of the pressure vessel could be analyzed using the fiber fracture damage threshold according to the MAE parameters.