Characteristics of Stress Wave Propagation of Carbon Fiber/Epoxy Laminates Fabricated by High-speed Automated Fiber Placement

Study of stress wave is of great significance to investigate the formation mechanism of manufacturing defects and nondestructive testing technology. Aiming to reveal the characteristics of stress wave propagation of carbon fiber/epoxy tows in high-speed automated fiber placement (AFP), in this paper, stress distribution and strain energy density (SED) of laying tows are calculated using the finite element method (FEM). The waves velocity and waves equation of carbon fiber/epoxy composite are obtained using the least square method and numerical analysis. Furthermore, characteristics of stress wave propagation under the different processing parameters and laying time are presented, and laws of peak and stability of stress waves response to different compaction force and laying speed are discussed. Finally, a group of processing parameter (S=33m/min, F=300KPa) is determined which could control the stress waves and release the strain energy efficiently.