Search

Owing to the increasing demand for high performance and lightweight materials, fiber metal laminates (FMLs) have become the alternative materials to replace metallic alloys. When the environmental friendliness of the materials is taken into consideration, plant fibers have shown an excellent potential to be employed as the reinforcements in FMLs. This work describes the mechanical behavior of kenaf and pineapple leaf fibers (PALF) reinforced metal laminates with various fiber contents, ranging from 10 wt% to 50 wt%. Fiber metal laminates were formed through the coalescence of metallic skin layers with the composite as the core. The mechanical tests were then conducted to study the tensile, flexural and Charpy impact properties of the structures. From the findings, it was concluded that both the kenaf and PALF based FMLs showed the optimum mechanical properties when the fiber content was fixed at 30 wt%. In addition, PALF based FMLs had shown higher mechanical properties over kenaf based FMLs. At a fiber content of 30 wt%, the tensile and flexural strength of PALF based FMLs were respectively 6.18% and 3.44% higher than kenaf based FMLs. In terms of impact properties, the impact strength of PALF based FMLs was 5.06% and 40.73% higher than kenaf based FMLs in the flatwise and edgewise orientations. [ABSTRACT FROM AUTHOR]

Fibre metal laminates (FMLs) are the contemporary sandwich materials that have been employed in the aerospace industries. The commercially available synthetic fibre based FMLs have shown excellent fatigue, impact and specific properties over those of metallic alloys. In order to explore the potential of environmental friendly cellulosic based materials, this research work aims to characterise the mechanical properties of novel woven pineapple leaf fibre reinforced metal laminates which were prepared through the hot compression moulding technique. For the comparison purpose, the mechanical properties of woven pineapple leaf fabrics and pineapple leaf fibre reinforced composite laminates were determined as well. It was concluded that the pineapple leaf fibre reinforced metal laminates evidenced salient mechanical and specific properties over pineapple leaf fabrics and composites. The specific tensile strength of metal laminates was 230.87% and 62.21% higher than those of the pineapple leaf fabrics and composite laminates whereas the specific flexural strength of metal laminates was 174.91% higher than composite laminates. Besides that, metal laminates also showed an impact strength of 91.49 kJ/m2 which was 143.13% greater than that of the composite laminates. The results indeed showed that the pineapple based FMLs could be considered as the promising and sustainable sandwich materials in future structural applications. [ABSTRACT FROM AUTHOR]

Fibre metal laminates are advanced sandwich materials that offer various outstanding properties over conventional metallic alloys and composites. This research study intends to investigate the effects of weaving architectures and stacking configurations on the mechanical properties of fibre metal laminates based on kenaf/pineapple leaf fibre. Fibre metal laminates were fabricated through the hot moulding compression technique. Mechanical tests were performed on the kenaf/pineapple leaf fibre-based fibre metal laminates. In accordance with the findings obtained, hybridisation had led to the improvement in the mechanical properties of fibre metal laminates in comparison with [K/K/K] fibre metal laminates. Overall, twill woven-ply [P/P/P] fibre metal laminates showed the highest tensile and flexural strength, which was 14.53% and 33.50% higher than twill woven-ply [K/K/K] fibre metal laminates, respectively. Besides, the twill woven-ply [P/P/P] fibre metal laminates also displayed the highest impact strength and indentation properties compared to other non-hybrid and hybrid fibre metal laminates. When comparing the fibre metal laminates with different weaving architectures, twill woven-ply fibre metal laminates were shown to have higher mechanical properties over those of plain woven-ply fibre metal laminates. [ABSTRACT FROM AUTHOR]

The use of polymer-based composites has been gaining popularity in the industry over the last few decades. Their high strength to weight ratio and high fatigue resistance make these composites the preferred materials for a wide variety of applications. The current trend has inclined towards hybrid fibre reinforced composites owing to their outstanding characteristics compared to non-hybrid composites. Numerous research works have been conducted to study the fatigue life behaviour of such composite materials. This study addressed the monotonic and dynamic performance of non-hybrid and hybrid natural fibre based composite materials, and the factors that influence their fatigue performance, along with the stiffness decay of each composite material. Most studies have shown the superior potential of using natural fibres in place of synthetic fibres in those critical applications that involve tensile and cyclic loading. [ABSTRACT FROM AUTHOR]

Hybrid composites have shown innumerable benefits to the research communities in terms of environmental friendliness and mechanical properties. This research study presents the mechanical characterization and moisture uptake of kenaf/pineapple leaf fiber‐reinforced polypropylene hybrid composites with several relative fiber ratios. A comparison was also made between nonhybrid and hybrid kenaf/pineapple leaf fiber‐reinforced composites to investigate the hybridization effect. In this work, the composite materials were fabricated via the hot compression technique. Mechanical tests were performed to obtain the tensile, flexural, and Charpy impact properties of nonhybrid and hybrid kenaf/pineapple leaf fiber‐based composites. The water absorption characteristics were then obtained by immersing the composite materials in the water until the saturation point was reached. The findings concluded that the mechanical properties and moisture uptake behaviors of the composites were improved through the hybridization. The hybrid composites with a relative fiber ratio of 25:75 were particularly promising with the improvement of 10.90% in tensile strength; 16.13% in flexural strength; and 6.80% in impact strength in both flatwise and edgewise orientations compared to nonhybrid kenaf‐based composites. Meanwhile, the diffusion coefficient of hybrid composites (25:75) was 56.12% lower than nonhybrid pineapple leaf fiber‐based composites. Thus, the results indeed demonstrated that the balance between mechanical properties and moisture sensitivity can be obtained through the hybridization of kenaf and pineapple leaf fiber in the composite materials. [ABSTRACT FROM AUTHOR]

The failure modes and energy absorption of square and round carbon/aramid multiple-segment tubes under quasi-static axial crushing were investigated. Cavity-shaped initiators were used to trigger inward crushing. The findings showed that for the same material lay-up, round tubes outperformed square tubes. The ability of the tube bottom segment to first crush symmetrically within the initiator had significant effects on the subsequent deformation modes of the tube. Among the tubes used in this study, those possessing graded stiffness with lower stiffness material at the initiator end and higher stiffness material at the crush end, crushed more uniformly within the initiator before folding progressively upward, displaying high energy absorption. [ABSTRACT FROM AUTHOR]