Multiscale Characterization of Nanoengineered Fiber-Reinforced Composites: Effect of Carbon Nanotubes on the Out-of-Plane Mechanical Behavior

Abstract

The mechanical properties of the matrix and the fiber/matrix interface have a relevant influence over the mechanical properties of a composite. In this work, a glass fiber-reinforced composite is manufactured using a carbon nanotubes (CNTs) doped epoxy matrix. The influence of the CNTs on the material mechanical behavior is evaluated on the resin, on the fiber/matrix interface, and on the composite. On resin, the incorporation of CNTs increased the hardness by 6% and decreased the fracture toughness by 17%. On the fiber/matrix interface, the interfacial shear strength (IFSS) increased by 22% for the nanoengineered composite (nFRC). The influence of the CNTs on the composite behavior was evaluated by through-thickness compression, short beam flexural, and intraply fracture tests. The compressive strength increased by 6% for the nFRC, attributed to the rise of the matrix hardness and the fiber/matrix IFSS. In contrast, the interlaminar shear strength (ILSS) obtained from the short beam tests was reduced by 8% for the nFRC; this is attributed to the detriment of the matrix fracture toughness. The intraply fracture test showed no significant influence of the CNTs on the fracture energy; however, the failure mode changed from brittle to ductile in the presence of the CNTs.

Ultrafast carbon nanotubes growth on recycled carbon fibers and their evaluation on interfacial shear strength in reinforced composites

“…The first phenomenon consists of areas of CNTs with a good interface between the fibers and resin (Fig. 7f), where the adherence of CNTs is good with respect to both the fibers and resin [46][47][48][49] . However, the second phenomenon appears in areas, such as those shown in Fig.…”

Effect of 0.5% CNT reinforcement of a glass fiber composite on strength and cyclic damage induced by transverse and out-of-plane compressive loads

“…To increase the out-of-plane mechanical resistance of composite materials, the properties of both the matrix and fiber-matrix interface should be improved. Several authors [23][24][25][26][27] considered adding carbon nanoparticles to composite materials and concluded that this approach improves the properties of the fiber-matrix interface and toughness of the matrix. For instance, Boroujeni and Al-Haik 28 obtained a 20% and 50% increase in tensile strength and fatigue life of a carbon FRC with carbon nanotubes (CNTs) compared with the original material.…”

“…Gonzales and Llorca 16 show that the increase in IFSS directly influences the transverse compressive strength. Medina et al 24 incorporated a masterbatch of MWCNTs in a glass FRC and improved the IFSS by 24%. Later, Bedi et al, 37 found an increase of the IFSS by grafting CNTs onto the surface of carbon fiber.…”

The Effect of High Loaded Multiwall Carbon Nanotubes in Natural Rubber and Their Nonlinear Material Constants

“…Phomrak and Phisalaphong [18] attempted with bacterial cellulose (BC) to reinforce the NR latex and concluded that the tensile strength was increased 94% higher than pure NR latex. Medina et al [19] prepared a glass fiber reinforced composite using CNTs doped epoxy and concluded that incorporation of CNTs increased the hardness by 6% and decreased the fracture toughness by 17%.…”