Acoustic Emission Behavior of Carbon Fiber Bundle Under Tensile Load

Background: Acoustic emission (AE) is widely used to study the progressive damage of composite materials. Traditionally, the AE method focuses on assessing structural damage by experimentally testing AE signals. However, the application of mechanical methods to theoretically predict AE signals during the progressive damage process of dry fiber bundles has been limited. Objective: The primary objective of this study is to establish a theoretical method for predicting AE signals during the tensile fracture process of dry fiber bundles. Methods: This model comprises three key components: (1) Single Fiber Fracture Dynamics Model: This component analyzes the motion of the fracture cross-section at the moment of fiber breakage. (2) Point Sound Source Model: Utilizing the motion of fiber cross-sections as a source, this model analyzes the acoustic signals generated during one single fiber fractures. (3) Monte Carlo Model: This model simulates the progressive fracture of the dry fiber bundle by aggregating the AE signals from individual fiber fractures. It generates a comprehensive time-domain signal profile by summing the contributions from each fracture event. Results: To validate the model's effectiveness and accuracy, a comparison was made with existing prediction models and available experimental data. The experimental results were found to be in good agreement with the theoretical predictions. Conclusion: This theoretical model has been thoroughly validated and can be applied to analyze AE signals in other brittle dry fiber bundles, providing valuable insights into their fracture behaviors.