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Electrospinning has by far proved to be the most successful method to spin high aspect and surface area to volume ratio nanofiber for multidisciplinary applications. Its application, however, as reinforcement in fiber reinforced polymer matrix composites (FRPC's) started from interlaminar fracture toughness improvement through interleaving. Since then, its usage both in short fiber and nonwoven mat formation has been phenomenally increased to tailor mechanical properties. This review paper focuses on application of nanofiber in multiscale reinforced epoxy matrix composites for mechanical performance. After a brief overview of electrospinning and spinning parameters, it presents a case for nanofiber as reinforcement with attendant mechanisms to develop insight into nanocomposite performance. Next, it summarizes and shares findings of studies, carried out in last 10 years, seeking to enhance tensile, flexural, interlaminar toughness, impact, and fatigue properties of epoxy composites through electrospun nanofiber reinforcement. Finally, it presents a perspective to gain headways in nanofiber reinforced FRPC's research through a variety of processing and material variables.

This study investigates the capacity of the nano-indentation method in the mechanical characterization of a heterogeneous dental restorative nanocomposite using experimental and computational approaches. In this respect, Filtek Z350 XT was selected as a nano-particle reinforced polymer nanocomposite with a specific range of the particle size (50 nm to 4 µm), within the range of indenter contact area of the nano-indentation experiment. A Sufficient number of nano-indentation tests were performed in various locations of the nanocomposite to extract the hardness and elastic modulus properties. A hybrid computational-experimental approach was developed to examine the extracted properties by linking the internal behaviour and the global response of the nanocomposite. In the computational part, several representative models of the nanocomposite were created in a finite element environment to simulate the mechanism of elastic-plastic deformation of the nanocomposite under Berkovich indenter. Dispersed values of hardness and elastic modulus were obtained through the experiment with 26.8 and 48.5 percent average errors, respectively, in comparison to the nanocomposite properties, respectively. A disordered shape was predicted for plastic deformation of the equilateral indentation mark, representing the interaction of the particles and matrix, which caused the experiment results reflect the local behaviour of the nanocomposite instead of the real material properties.

Composite-metal stack is an ideal combination of materials which unites the advantages of each dissimilar material in a substantial weight. However, drilling dissimilar materials has been a challenge since the composite-metal stacks are at demand in industries. It is important to choose the appropriate drill geometry regarding the stacking sequence and utilize proper machining parameters in order to achieve damage free and precession holes. This experimental study was conducted on dry drilling of CFRP/Al2024/CFRP (carbon fiber-reinforced plastic). Four types of twist drills with various geometries, both coated and uncoated, were utilized to study the effect of machining parameters on hole quality. It was observed that increasing feed rate entails an increase in entrance delamination, whereas exit delaminations and fiber fraying at 2nd CFRP exit diminished with increasing feed rate. It was also found that four facet tools performed better than two facet tools in terms of fiber delamination. Most accurate hole was attained on 2nd CFRP; however, it was found that increasing feed significantly affects the hole size on 1st CFRP.

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In the past few decades, Composite Sandwich Panel (CSP) technology significantly influenced the design and manufacturing of high performance structures. Although using CSP increases the reliability of structure, the important concern is to understand the complex deformation and damage evolution process. This study is focused on the mechanical behaviour of CSP under flexural loading condition. A setup of three-point bending test is prepared using three support span of 40, 60 and 80 mm. The loading was controlled by three different displacement rates of 1, 10 and 100 mm per minute to examine the effects of strain-rate on bending behaviour of CSP material. The beam span significantly affects the flexural stiffness of CSP panel. The load-deflection response of the panel shows two different portions, that representing equivalent elastic and plastic regions in both the core and facesheets components of CSP. The non-combustible mineral-filled core appears to be nonlinear in the elastic region, at high loading rate. Consequently the failure occurs as the core/facesheets interface suffers debonding.

Hybrid composites have become the focal point of research communities due to the balance in mechanical and ecological properties of such materials.Hybridization is an efficient technique to strengthen and enhance the performance of composite materials. In this research study, hybrid composites were prepared by embedding pineapple leaf and glass fibers in polypropylene polymers via the hot press molding compression technique. Mechanical tests were carried out to determine the tensile, flexural and Charpy impact properties of pineapple leaf/glass fiber-reinforced hybrid composite laminates. Additionally, water absorption test was also conducted to investigate the influence of hybridization on the moisture uptake of hybrid composites. In accordance with the findings obtained, the hybridization of pineapple leaf with glass fibers was found to improve the mechanical properties and moisture uptake sensitivity of the composite laminates. The [G/P/G] composite laminates are especially promising, having comparable mechanical strengths to those of non-hybrid [G/G/G] composite laminates. Meanwhile, the water absorption and diffusion coefficient of [G/P/G] composite laminates were 66.64% and 40.71% lower than non-hybrid [P/P/P] composite laminates. Based on the findings obtained, it is anticipated that the hybridization of pineapple leaf and glass fibers endows the composite laminates with lightweight characteristic, remarkable mechanical properties and low moisture uptake sensitivity while improving the environmental friendliness of the materials. Therefore, hybrid composites have indeed attested a very high potential to be used in transportation sectors.