Study on tensile properties of ultra‐thin‐ply carbon fiber‐reinforced composite laminates under static load

Abstract The thinning of carbon fiber‐reinforced composites has been shown to enhance their strength and damage resistance. In this study, cross‐ply and quasi‐isotropic laminate tensile experiments are conducted using composites with ply thicknesses of 24, 55, 75, and 100 μm to investigate the relationship between the strength of laminates and ply thickness. By analyzing the acoustic emission amplitude and energy signals during the loading process of the specimens, the damage evolution of each ply thickness composite under two different stacking methods is studied, revealing the failure mechanisms of the materials. The results show that under both cross‐ply and quasi‐isotropic stacking methods, the ultra‐thin‐ply composites exhibited higher strength. The thickness of ply has a significant influence on the fracture mode of the quasi‐isotropic laminates and the mechanical properties of quasi‐isotropic laminates are more affected by ply thickness than those of cross‐ply laminates. Highlights Quasi‐isotropic laminate strength is affected more by ply thickness than cross‐ply. Reduced ply thickness changes fracture mode in quasi‐isotropic laminates. Ultra‐thin‐ply composites exhibit flat fractures resulting in higher strength.