Interfacial toughening of carbon fiber reinforced polymer (CFRP) matrix composites using graphene oxide containing nanofibers

Download
2019
Çaylan, Cansu
The importance of carbon fiber reinforced polymer (CFRP) composites is increasing day by day in everyday life. While they have great importance owing to their high strength- and stiffness-to-weight ratios, these new materials still have some weak aspects which need to be improved. One of these aspects is ‘delamination’. To increase the delamination resistance, the most promising technique is the one that includes the use of nanofibers because of ease of process and no increase in total weight of composites. Recently, hybrid systems which combine the properties of two or more monolithic materials have attracted considerable attentions. This work focuses on the enhancement of interfacial toughness of CFRP composites using hybrid nanofibers which are graphene oxide containing electrospun nanofibers by using nylon 6 (N6)/polycaprolactone (PCL) polymers with different N6 mass ratios (60, 80, 100 wt %). With this aim, firstly, GO has been synthesized and after that homogeneous distribution of containing different size of GO (GO1: 466 nm, GO2: 230 nm, GO3: 165 nm) along the fiber have been studied. The results showed that N6 containing 2 wt % of GO2 provides the increase of G1c-in and G1c-prop values about 21% and 13% according to reference. Composites containing N6/PCL-60/40 with varying quantities of GO3 nanofibers, G1c values could not be increased because of the deterioration of the synergistic relationship between ‘debonding/fiber bridging’ mechanisms. Highest G1c value was obtained with N6/PCL-80/20 containing 0.5 wt % of GO2 composite with a 26% improvement on the G1c-in and 42% on that of G1c-prop.

Suggestions

MECHANICAL PROPERTIES OF REPAIRED CARBON FIBER REINFORCED POLYMER COMPOSITES
Sonat, Emine Evren; Özerinç, Sezer; Department of Mechanical Engineering (2021-12-10)
Carbon fiber reinforced polymer (CFRP) composites are increasingly used in the aerospace industry due to their high specific strength compared to conventional metallic materials. However, a significant shortcoming of these composites is their increased susceptibility to damage. Structural repair is a common method to restore the load-carrying capacity of a damaged part when the damage size exceeds the pre-defined tolerances. Scarf and stepped bonded repair methods are the primary choice for cases that requi...
Mechanical, electrical and thermal properties of carbon fiber reinforced poly(dimethylsiloxane)/polypyrrole composites
Cakmak, G; Kucukyavuz, Z; Kucukyavuz, S; Cakmak, H (2004-01-01)
Conductive and flexible carbon fiber (CF) reinforced polydimethylsiloxane (PDMS)/polypyrrole (PPy) composites were synthesized electrochemically. Electrochemical synthesis was performed at + 1.1 V using p-toluenesulfonic acid as supporting electrolyte and water as solvent. Composites were characterized by thermal gravimetric analysis, scanning electron microscopy (SEM), conductivity measurements and mechanical tests. Conductivities of composites were observed in the range of 2.2-4 S/cm. SEM studies show tha...
Polystyrene-based and carbon fabrİc-reİnforced polymer composİtes containing carbon nanotubes: preparation,modification and characterization
Erkmen, Berrak; Bayram, Göknur; Department of Chemical Engineering (2020-11-23)
Carbon Fabric-Reinforced Polymers (CFRPs) attract attention due to their high mechanical properties, electrical conductivity, and providing weight reduction solutions in aerospace, automotive, marine, and energy industries. Since recycling, long processing times, non-visible damages, and complex repair procedures of thermoset-based CFRPs cause problems, studies are performed on the application of thermoplastic-based CFRPs. This study aims to produce polystyrene (PS)-based and carbon nanotubes (CNTs) and car...
Failure behavior of on-site repaired CFRP laminates
Sonat, Evren; Bakır, Mete; Özerinç, Sezer (2023-05-01)
On-site repairs of carbon fiber reinforced polymer (CFRP) composites involve out-of-autoclave curing, which increases the defect density and reduces the mechanical properties. This work aims to understand the strength and the associated failure mechanisms of on-site repaired woven CFRP laminates through experiments and simulations. A series of wet lay-up and prepreg step repaired specimens produced according to standardized aerospace procedures were tested under uniaxial tension. Wet lay-up repair provided ...
Experimental determination of tool wear in routing and trimming of CFRP composites
Peker, Zühal; Akkök, Metin; Kılıç, S. Engin; Department of Mechanical Engineering (2015)
In order to fulfill growing demand for lighter aircraft, Carbon fiber reinforced polymers (CFRP) have been developed, which differ from metals with regards to their machinability characteristics. The main problem in machining process is the damage caused by delamination of CFRP materials which need to be both cut and shorn of fibers at the same time, since they are remarkably abrasive in nature. This research aims at accessing the most appropriate cutting condition with less tool wear in routing and trimmin...
Citation Formats
C. Çaylan, “Interfacial toughening of carbon fiber reinforced polymer (CFRP) matrix composites using graphene oxide containing nanofibers,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Chemical Engineering., Middle East Technical University, 2019.