Summary

In most of the cases, the filler addition and its property enhancement with respect to its weight percentage inclusion in the composite-based investigations were completed with the support of experimental tests. The reasons behind the huge involvement of experimental test are its good reliability in the outcomes and the generation of test specimen in a controlled manner [6]. But in this work, the FEA-based computational simulations are used in the investigation of nanocomposites under tensile load conditions with a huge support from these aforementioned references. FEA- based nanocomposite analyses face two kinds of foremost difficulties, which make the outcomes unreliable. The two major difficulties principally involved in the FEA simulations are complexity in the construction of nanocomposite with its filler weight inclusion and obtaining boundary conditions needed for this complicated analyses. Thus, the strongest help is needed for these complicated analyses and hence the standard literature survey helped soundly in order to solve this structural simulation in an efficient manner [10]. Chiefly, the following conditions are obtained from the standard literatures: primary mechanical properties of MWCNTs and SWCNTs, good ranges of weight inclusion of filler in percentages, the manner in which CNTs are added in the perspective of computational analyses, external loading conditions, and support types. In this article, universal testing machine (UTM)-based experimental test is also engaged for the purpose of validation of computational results. In the experimental test phase, the following data are important: test specimen construction methodology, suitable environmental conditions, and lading details that are extracted from the standard literatures [13].

Methodology Used and Its Validation

Experimental Testing

Materials Used and Dimensions of Specimen

Experimentally, carbon fiber is short-listed for reinforcement, which plays a predominant role in the load-carrying function. Fundamentally, carbon fibers are dependent on graphene, which is primary element of carbon. Dry fabric and prepreg are the major available forms of carbon fiber. The natural color of carbon fiber is gray or black. Epoxy resin is used as a matrix, which is basically fit for all the available forms of carbon fiber. Epoxies come under thermosetting resin, and the viscosities of epoxy are available in all the stages from liquid to solid. Apart from carbon fiber and epoxy, CNTs contribute a lot in this work. A CNT is a tube-shaped material made of carbon, having a diameter that is measured on the nanometer scale [1]. In this experimental testing, MWCNT is used as mixtures in the CFRP for property enhancement. Five percent content of MWCNT is added to epoxy and then test specimen processes are

Materials used for fabrication

FIGURE 9.1 Materials used for fabrication.

executed as per the standard procedure. The specifications for the design considerations of tensile test are followed as per the ASTM Standard (D3039), in which the length, width, and thickness of the specimen are 230, 25, and 5 mm, respectively. Figure 9.1 shows the preparation of nanocomposite for testing.

Preparation of Test Specimen

The contents used in this nanocomposite are 60% of carbon fiber (263 g) as reinforcement, 40% of epoxy resin with hardener, and 5% of MWCNTs as a matrix. After successfully finalizing the content, the fabrication process is finalized. Comparatively, compression molding process is more suitable for the nanocomposite generation because of its output reliability and user-friendly nature, which make it fit for the construction of all kinds of composite material. The common and general procedures are followed in this nanocomposite construction, in which 3 psi pressure is used for the compression purpose [1]. Figure 9.2 shows the typical process involved in the compression molding, and Figure 9.3 reveals the output of compression molding process. And then the final products are shown in Figure 9.4.

Testing Results

Mechanical test is generally used to provide a complicated experience to test specimen, which provides the tackling technique in order to overcome complicated environments. Tensile, bending, and impact tests are primary evaluation methodologies involved in the structural analysis, in which tensile test is the base and universal engineering evaluation methodology to attain and analyze the structural parameters. The important structural parameters are modulus of elasticity, % area of reduction, yield strength, % elongation, and ultimate strength. The working environment of the tensile test is loaded in axial direction at one end and the other end of the test specimen is fixed at UTM jars. The detailed pictorial representations are shown in Figure 9.5. The known values of the tensile test are gauge length and perpendicular area of the test specimen, which supported a lot in the calculation of stress and strain of test material [11]. The tensile tests are conducted in the room temperature and the results are noted, which is also shown in Figure 9.6, and the comprehensive data of this test outputs are listed in Table 9.1.

Compression molding process

FIGURE 9.2 Compression molding process.

Test specimen preparation

FIGURE 9.3 Test specimen preparation.

Test specimens

FIGURE 9.4 Test specimens.

Universal testing machine with test specimen

FIGURE 9.5 Universal testing machine with test specimen.

Load vs elongation

FIGURE 9.6 Load vs elongation.

TABLE 9.1 Tensile Test Report

Input Data

Output Data

Specimen shape: dog bone shape

Load at yield: 91.10 kN

Specimen type: nanocomposite

Elongation at yield: 1.5300mm

Specimen description: carbon fiber+ MWCNTs

Yield stress: 581.600 N/mm!

Specimen width, thickness, length:

25, 10, 175 mm

 
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