Effect of gaps/overlaps induced waviness on the mechanical properties of automated fiber placement (AFP)-manufactured composite laminate

Abstract

Automated Fiber Placement (AFP) process is widely used to produce lightweight composite components owing to its excellent flexibility and efficiency. However, the out-of-plane fiber waviness induced by gaps and overlaps inevitably formed in the AFP process lack experimental studies. Therefore, an experimental research is proposed to study the influence mechanism of out-of-plane fiber waviness. Herein, based on the description of the shape of the fiber waviness, the relationship between the magnitude factor and the axial elastic modulus of laminate with fiber waviness is established. By embedding gaps and overlaps in the layup, a new approach to manufacturing composite laminate with fiber waviness of sine wave and sine-like wave is proposed, and the rationality of the theoretical analysis on the elastic properties of laminate with fiber waviness is verified. Finally, the effect of the magnitude factor on the mechanical properties of composite laminate is obtained by tensile and compression test. Experimental results show that the tensile and compression properties of laminate decrease significantly with the increase of magnitude factor. The effect of sine-like wave on mechanical properties is similar to that of sine wave, and it is feasible to splice sine-like wave into sine wave for mechanical property analysis.

Smart Roller: Soft Sensor Array for Automated Fiber Placement

“…If untreated, layup defects create resin-rich areas and/or porous areas, as well as deviations in fiber orientation, which ultimately has a detrimental effect on the mechanical properties of final cured parts such as tensile, compressive, and interlaminar properties (for instance, refs. [22,23]).…”

Characterizing the stress relaxation behavior of unidirectional prepreg through a parallel fractional-order viscoelastic model

“…During the preforming process, inappropriate molding parameters can result in defects such as wrinkles and fiber bending, leading to a deterioration in the mechanical performance and service life of the product [9][10][11]. Among the molding parameters, pressure holds significant importance.…”

Determination of lubricating behavior of resin during the sliding process of unidirectional prepreg

“…During this process, prepreg sheets are fabricated through automated layup technologies, subsequently formed to designated shapes under applied pressure [1]. However, some defects like wrinkling and fiber misalignments may be produced in this molding process, which can lead to reductions in the mechanical properties of the final product [2,3]. Researchers believe that the behavior of inter-ply slipping plays a pivotal role in defect generation [4][5][6].…”