Structural health monitoring of natural fiber‐based hybrid composites

Abstract The purpose of this article is to evaluate mechanical behavior, detect early damage, and understand failure mechanisms of natural fiber composites using acoustic emission testing (AE). Natural fiber composites are increasingly used in various applications due to their low cost, renewable and biodegradable nature, and excellent mechanical properties. However, their mechanical behavior and failure mechanisms are complex and must be better understood, and nondestructive testing methods are required to evaluate their performance. The article discusses the AE behavior of banana‐ramie‐epoxy composites in tensile tests for the first time. The composites were fabricated by compression molding with 4‐layer banana‐ramie epoxy at 0° stacking. The AE signals were recorded and analyzed during the test using a piezoelectric high‐frequency sensor to identify the different types of AE events. The results showed that the composites exhibited high levels of AE activity at different stages. AE signals were closely related to the damage mechanisms occurring in the composites, such as fiber/matrix debonding, fiber breakage, and matrix cracking. This research results also suggest that AE can help optimize the design and performance of novel composites in practical applications.