MECHANICAL CHARACTERIZATION OF GRAPHENE NANOPLATELETS INTEGRATED NON-CRIMP CARBON FIBER LAMINATED COMPOSITE LAMINATES

The use of lightweight composite materials has increased exponentially during the last few decades. The lightweight structural composite components are typically manufactured using an epoxy-based matrix. Non-Crimp Fabric (NCF) provides excellent mechanical properties, and the fabrication cost is substantially lower than conventional composite manufacturing methods. The matrix forms a thin layer between the fibers which bonds, transfers force, and displace adjacent layers. Compared to carbon fibers, the strength and stiffness of the matrix are much lower. When the structure is subjected out of plane loading, the matrix layer tends to fail and separates from the adjoining fiber layers. Eventually, the separation of layers forms stress concentration resulting in interlaminar delaminations in the composite laminates. To enhance the matrix properties, nanomaterials are added to the epoxy system. Due to their high aspect ratio superior properties, the carbon nanofillers such as carbon nanoparticles, Carbon Nanotubes (CNTs), Carbon Nano Fibers (CNFs), Graphene nanoparticles/nanoplatelets (GnP’s) incorporated epoxy composites offer new avenues to improve the multifunctional properties of polymer matrix composites. Most of the researchers used epoxy nanocomposites to investigate the properties of the inclusion of nanoparticles into the composite. One of the challenges of using these nanomaterials is the dispersion without agglomeration. The study indicates that using the traditional Vacuum Assisted Resin Transfer Method (VARTM) process is difficult to fabricate the nanoengineered composite laminate, as nanoengineered epoxy blocks resin flow when it enters the micro gap between the fibers. In the present research, the laminates were manufactured by first fabricating nanoengineered prepregs to overcome these challenges. GnP’s of 0.25, 0.5, 0.75, and 1 % weight of matrix respectively were used to formulate nanoengineered prepregs using hand layup prepreg fabrication technique and were semi-cured using a mechanical press. These prepregs were then used to fabricate the nanoengineered composite laminate. Static tension tests were performed to investigate the effects of graphene nanoplatelets loading on the modulus, strength, and Mode I fracture toughness test was performed to find interlaminar fracture toughness. The impact of GnP’s loading on the Glass Transition Temperature (Tg) was estimated using Dynamic Mechanical Analysis (DMA).