Evaluation of Progressive Damage and Identification of Failure Mechanisms in Carbon Fiber Woven Composites via Tensile Test

Due to the widespread application of carbon fiber woven composites in aerospace, automobile and industrial area, understanding the damage evolution of carbon fiber woven composites are the most important aspect with respect to service life. Damage initiation and propagation of composites require greater mass force and little force can cause the failure of the structure on composite materials once exceeding the critical threshold at the onset of damage. A better knowledge of dynamic behaviors for damage growth can help to improve structural optimization design and production of high-performance composites. In this study, the mechanical behaviors of composites were analyzed under uniaxial tensile loading tests. Simultaneously, the chronology of internal damage evolution process in composite was detected by acoustic emission (AE). The AE signals recorded is filtered by the Maxmin Distance algorithm and following the k-means algorithm was used to achieve damage modes recognition. Based on microscopic observations and frequency range, the three clusters are correlated with different damage mode like matrix cracking, fiber/matrix debonding and fiber breakage. In addition, the Sentry Function (SF) affected by the mechanical behavior of the material was adopted to investigate evolution of the acoustic events and verify the results of clustering results.