A review of multiscale composite manufacturing and challenges

Abstract

As the utilization of advanced composites in structural applications grows, the need for improving their through-thickness properties becomes imperative. Although the behavior of composite laminates under structural and thermal loads has received much attention with their growth in safety critical structures, more effort needs to go into selectively improving their electrical and thermal conductivities. Additionally, the ability to manufacture composite structures that can inherently monitor their own health will be exceedingly beneficial. This paper provides an overview of advances made towards multiscale composite manufacturing. Multiscale composites, especially with the use of carbon nanotubes, have been sought to provide enhanced structural (through-thickness) properties and increased electrical and thermal conductivities. This report will review the state of art in the manufacturing of multiscale composites, their scalability, and their inherent potential for multifunctionality. Current techniques mostly result in the application of carbon nanotubes throughout the entire laminates, rather than in selected areas. Subsequently, one of the main barriers, to the widespread use of carbon nanotube-applied composites, is an efficient mass-producible manufacturing process. This paper attempts to highlight the current knowledge gaps in this critical area of composites manufacturing.

Simultaneous reinforcement of matrix and fibers for enhancement of mechanical properties of graphene‐modified laminated composites

“…Graphene nanomaterials such as single‐ and multi‐walled carbon nanotubes (MWCNTs), graphene nanoplatelets (GNPs), graphene oxide (GO), and reduced‐GO (rGO) are light nano‐sized small materials with excellent thermo‐electro‐mechanical properties . When conventional fiber‐reinforced laminates are modified with graphene nanomaterials, new materials with improved mechanical, thermal and electrical properties may be developed . Carbon nanotubes are an allotrope of sp2 hybridized carbon with one or several tubes in concentric cylinders .…”

“…Typical manufacturing methods to fabricate laminates composite parts are vacuum‐assisted resin transfer molding (VARTM) , autoclave molding , compression molding (including hot pressing) and hand lay‐up . A review of some of the techniques for manufacturing of multiscale composite and challenges can be found in the work of McCrary‐Dennis and Micah . Due to minimal pressures, ambient temperature and low‐cost tooling involved, VARTM is the method of choice for large, complex parts like boat hulls or large transportation parts like bus bodies .…”

“…There is a need for developing new manufacturing methods to fabricate polymer resins enhanced with carbon nanomaterials for applications where weight, stiffness and strength are critical, and to assess the nanoparticle reinforcement achieved compared with conventional laminates such as glass fiber and carbon fiber-reinforced polymer composites. Multiscale nanocomposites are a novel class of multifunctional composite materials that have received special attention because of their improved properties at very low loading levels compared with conventional filler composites [1][2][3][4][5][6][7][8]. Although conventional polymer composite materials reinforced by continuous fibers are strong in in-plane direction, they are usually weak against matrixdominated failures.…”

Multiscale Polymer Composites: A Review of the Interlaminar Fracture Toughness Improvement

“…As the name suggests, "multiscale" composites comprise reinforcements at varying scales, such as continuous or discontinuous fibers of the order of mm, along with microscale fibers and/or nanoscale fillers or tubes. They are manufactured by merging nanoscale-sized fillers (e.g., CNTs) with traditional fiber reinforcements like glass and carbon [150,151]. The fiber resists in-plane load whereas the nanoscale reinforcement improves the performance of the through-thickness direction.…”

The use of noncovalently modified carbon nanotubes for preparation of hybrid polymeric composite materials with electrically conductive and lightning resistant properties

“…Polymeric composite structural materials (PCM) with functional properties, such as electrical conductivity, lightning resistance, and EMI shielding, represent one of the foreground tasks in state‐of‐the‐art materials science . One of the possible ways in the developing of such materials is a fabrication of hybrid polymer composite materials (HPCM) filled both with reinforcing (glass and/or carbon fiber) and functional fillers such as carbon nanotubes (CNTs), carbonaceous nanoparticles, metal/carbon nanocomposites . In several articles, the possibility of the use of highly conductive layers, based on CNTs, on HPCM surface with the goal of increasing of lightning strike protection has been discussed.…”