Effect of stacking angles on mechanical properties and damage propagation of plain woven carbon fiber laminates

Damage propagation induced failure is a predominant damage mechanism. This study is aimed at assessing the damage state and damage propagation induced failure with different stacking angles, of woven carbon fiber/epoxy laminates subjected to quasi-static tensile and bending load. Different stages of damage processing and damage behavior under the bending load are investigated by Scanning Electron Microscopy (SEM). The woven carbon fiber/epoxy laminates which are stacked at six different angles (0 degrees, 15 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees) with eight plies have been analyzed: [0](8), [15](8), [30](8), [45](8), [60](8), [75](8). Three-point bending test and quasi-static tensile test are used in validating the woven carbon fiber/epoxy laminates' mechanical properties. Furthermore, the damage propagation and failure modes observed under flexural loading is correlated with flexural force and load-displacement behaviour respectively for the laminates. The experimental results have indicated that [45](8) laminate exhibits the best flexural performance in terms of energy absorption duo to its pseudo-ductile behaviour but the tensile strength and flexural strength drastically decreased compared to [0](8) laminate. Finally, SEM micrographs of specimens and fracture surfaces are used to reveal the different types of damage of the laminates with different stacking angles.