Document Details
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Document Type |
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Thesis |
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Document Title |
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ENHANCING THE MECHANICAL PROPERTIES OF AEROSPACE FIBER REINFORCED POLYMER COMPOSITE MATERIALS USING NANOPARTICLES تحسين الخواص الميكانيكية لمواد الطيران المركبة المقوّاة بالألياف بإضافة جزيئات النانو |
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Subject |
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Faculty of Engineering |
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Document Language |
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Arabic |
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Abstract |
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Nanoparticles (NPs) have attracted wide interest in the modern era due to their outstanding and unique physical, chemical and multifunctional properties. Currently, NPs are being added to polymer matrix systems (PMSs) to enhance the mechanical properties of fiber reinforced polymer (FRP) composites. Out of the most widely investigated types of NPs, carbon nanotubes (CNTs) and graphene nanoplatelets (GNPs) are the most promising NPs. One area of potentially great improvement is within antisymmetric layups that can exhibit high matrix strains. However, NPs uniform dispersion, strong bonding interface between NPs and the matrix, selecting the proper type of NPs and the weight ratio (wt.%) are some challenges that need to be overcome in order to produce high performance fibers and NPs reinforced polymer (FNRP) composites.
Consequently, a three-stage comprehensive experimental investigation is conducted in order to characterize the level of improvement in the mechanical properties of FRP composites that are enhanced with either GNPs, or single walled carbon nanotubes (SWCNTs) or multi-walled carbon nanotubes (MWCNTs). In the first stage, aided by Raman spectroscopy, the manufacturing process is optimized through parametric testing of the sonication amplitude and time. In the second stage, NPs type, NPs wt.% ratios, and the pre-treatment liquid type are optimized through tensile testing of NPs reinforced polymer (NRP) nanocomposite specimens. The derived tensile properties include the ultimate tensile strength (UTS), the elastic modulus (E), true strains and engineering strains (proportional limit, yield and failure strains) while the NPs dispersion quality is investigated using transmission electron microscopy (TEM). In stage three, using an antisymmetric but balanced layup sequence (+45/ 02 / 902 / 02/-45), glass FRP (GFRP) laminates as well as glass fibers and NPs reinforced polymer (GFNRP) laminates are manufactured using a wet layup technique. In addition to the mentioned tensile mechanical properties, flexural strength, interlaminar strength (ILSS) and fatigue properties are derived and compared for neat GFRP composite, SWCNTs-based GFNRP nanocomposite and GNPs-based GFNRP nanocomposite. Stages one and two results indicate that the optimum sonication amplitude and time of NPs in ethanol are 40% and 60 minutes, respectively while the optimum NP type and ratio are SWCNT and 0.1 wt.% respectively. Stage three results indicate that the use of SWCNTs and GNPs produced optimum GFNRP nanocomposites UTS and ILSS respectively. On the other hand, GFNRP nanocomposites flexural strength is equally improved by using either SWCNTs or GNPs. In addition, fatigue life of GFNRP nanocomposites are surprisingly enhanced by about three and twelve times when GNPs and SWCNTs are used, respectively. Moreover, statistical analysis using t-test approach is used to support the decision making of finding out experiments conclusions.
Finally, numerical analysis method is carried out to predict the mechanical properties of NRP and GFNRP nanocomposite materials and validate the used models based on the experimental results. It is concluded that there is large difference between numerical and experimental results is due to many effective parameters such as NPs dispersion, actual morphology of NPs and interphase properties are not included in the applied micromechanical models. Therefore, the numerical models need to be revised to include all these parameters. |
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Supervisor |
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Dr. Mostefa Bourchak |
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Thesis Type |
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Doctorate Thesis |
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Publishing Year |
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1439 AH
2018 AD |
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Added Date |
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Tuesday, March 6, 2018 |
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Researchers
| عبد الله محمد القرني | Al-Garni, Abdullah Mohammad | Researcher | Doctorate | |
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