查看更多>>摘要：The special edition presents readers with the latest research results in the field of modern composite materials. In articles of Chapter 1: Sustainable Bio-Based Composites explore techniques of the development and application of composites derived by reinforcing the base materials with natural fibres from renewable bioresources. The importance of reducing the impact on the environment while simultaneously preserving the strength characteristics of the resulting material, as well as ensuring the structural integrity and operational characteristics of structures made from it, is highlighted.
查看更多>>摘要：In order to increase the utilization of polymer composite technology, natural fiber reinforced composites are required. Because of its exceptional mechanical qualities, bamboo culm fiber in hybrid composites has drawn the rigorous attention of researchers and producers. Gigantochloa Scortechinii, a particular species of bamboo, was obtained for this investigation from the Bukit Larang hamlet in Melaka, Malaysia. In these trials, a 5 mm thick metal mold was used to manually lay-up epoxy, chopped strand mat, and bamboo fiber. The 355 μm and 500 μm composite bamboo fibers were made. There was a range in the percentage of bamboo fibers from 1% to 5%. After that, the specimens were examined utilizing a variety of methods, including as impact, flexural, and tensile testing. Comparing the 500 μm bamboo hybrid composite to the 355 μm bamboo hybrid composite, the results showed improvements in tensile and impact strength of 22.3-42.3%. For the flexural strength, however, the reverse trend was seen (34.8-36.25%). These results imply that bamboo fiber, which is based on a hybrid composite of chopped strand mat and epoxy, produces outstanding mechanical qualities and can be a good substitute for reinforcing fibers made of composite materials.
查看更多>>摘要：The purpose of this study was to determine the tensile, fiexural, and impact strength of coir composites as fishing boat wall materials. The stages of this study were: (1) preparation, procurement of materials, coir treatment, composite manufacture, testing, and discussion. Before being used as a composite reinforcement, coir was soaked in an alkali solution with a concentration of 20% for 3 hours, then dried in an oven at a temperature of 90°C for 5 hours. Coir composites were made with three types, namely 20%, 25%, and 30% coir, respectively. After that, tensile, fiexural, and impact test specimens were made. Based on the test, the highest tensile and fiexural strengths were obtained in coir composites with a composition of 30% coir, respectively 21.04 MPa and 44.71 MPa, while the highest impact strength was obtained in a composition of 25% coir, namely 4.3 kJ/m2. It was concluded that the higher the composition of coir, the greater its strength.
查看更多>>摘要：This study investigates the water absorption characteristics of epoxy-based hybrid composites reinforced with natural sisal fibers and synthetic glass fibers. Four different stacking sequences of fiber layers: SSSS (four sisal layers), SSSG (three sisal layers and one glass layer), SSGG (two sisal layers and two glass layers), and SGGG (one sisal layer and three glass layers), were fabricated to assess their influence on moisture absorption properties. The water absorption percentages determined during testing of the compositions are averaged, showing a trend of decreased water absorption with an increase in the number of glass fiber layers. The SGGG configuration exhibits the lowest water absorption at 3.18%, while the SSSS configuration has the highest at 6.63%. This trend highlights the absorbent nature of sisal fibers and confirms the role of glass fibers in enhancing water resistance. Hybrid fiber reinforcements can therefore improve not only the mechanical properties of epoxy composites but also make them more environmentally friendly. Such materials provide a viable alternative to conventional plastics. Additionally, understanding the effect of stacking sequences on moisture absorption may enable future composite designs tailored for specific environmental conditions.
查看更多>>摘要：As the largest sago starch producer in the world, Indonesia has a very large amount of leftover waste from sago starch production, which is usually called sago pith waste (SPW). This large amount of waste has enormous potential to be utilized for other benefits and purposes. In this study, SPW was tested for use in manufacturing composite materials. The aim is to investigate the detailed properties of the composites that have SPW particles in them. Unsaturated polyester resin was used as the composite matrix, and three different SPW percentages were tested: 20%, 30%, and 40%. Tensile tests were performed on the composites, and three specimens were prepared for each SPW percentage variation. All nine specimens tested failed at the maximum given load. Either the maximum strain before the specimen failed or the ultimate tensile stress decreased with larger SPW percentages used in the composites. Further, SEM micrograph examination of selected fractured specimens successfully revealed the behavior and the morphology of SPW particles on the fractured surface.
查看更多>>摘要：Natural fiber has been used as a heat-insulating material for ages in Indonesia. On the other hand, there is plenty of sago pith waste (SPW) available since the nation is the world's top producer of sago starch. In this study, SPW was utilized in manufacturing composite materials, and their thermal properties were investigated. The unsaturated polyester resin was used as the matrix, and the composites were manufactured in three different SPW volume fractions: 20%, 30%, and 40%. The thermal properties were measured using a test setup box equipped with a 100 W lamp as a heat source. The thermocouple sensor DS18B20 was utilized to measure the necessary temperatures to determine the thermal conductivity of the composites. An Arduino microcontroller system connected to a computer was applied to manage the reading from the temperature sensors. The thermal conductivity was measured according to the temperature of the heat source. It was discovered that as the SPW volume fraction in the composites increases, thermal conductivity does as well at any lamp temperature. The measured thermal conductivity varied considerably; thus, taking the average may not be reliable as the error bars were larger than the average values. Further analysis of the measured temperature development revealed that the accurate thermal conductivity values lie within a very narrow range of lamp temperature, 50 ℃ < T_(lamp) <60 ℃.
IKRAMULLAH ZeinSAMSUL RizalH.P.S. ABDUL KhalilMOHD lqbal...
39-46页
查看更多>>摘要：Research on composites reinforced with abaca fiber is still being carried out. Research about fiber treatment, research about mixing abaca fiber with other natural fibers, or mixing abaca fiber with synthetic fiber, as well as the types of matrices used and research on differences in fiber orientation to determine its strength still being conducted. This is because abaca fiber is easy to find in Asia [l]-[4], and easy to produce. This research aims to study the mechanical properties of abaca fiber orientation on abaca fiber reinforced composite. The fiber is abaca fiber (Musa Textiles Ne) and the matrix is epoxy resin. The abaca fiber was treated with the alkaline solution for 2 hours and washed thoroughly, and dried after that. The abaca fiber is prepared in 3 orientations: the first is woven orientation, the second is unidirectional orientation, and the last is random orientation. The abaca fiber is then mixed with epoxy resin in a ratio of 40% abaca fiber and 60% epoxy resin and pressed to a thickness of 4 mm. According to the ASTM D638 standard, tensile strength testing was conducted, and flexural strength was conducted according to the ASTM D790 standard. The results show that the tensile strength of woven orientation is 63.1156 MPa and fiber with a unidirectional orientation is 62.4829 MPa, and fiber with a random orientation is 22.3517 MPa. The elastic modulus of woven, unidirectional and random orientations are 3.6425GPa, 3.9734 GPa, and 1.6449 GPa, respectively. Bending test results show that random orientation is more flexible than woven and unidirectional orientation, where the strain values are 0.0408 mm/mm, 0.0393 mm/mm, and 0.0369 mm/mm, respectively. The flexural modulus of the three different orientations is 0.8082 GPa for random orientation, 1.2176 GPa for woven orientation and 1.675 GPa for unidirectional orientation. It can be concluded that the tensile strength of woven orientation increases by 1% to unidirectional orientation and 182% to random orientation. Compared to the three different orientations, random orientation has higher bending properties than woven and unidirectional orientation, and woven orientation is still more flexible man unidirectional orientation.
查看更多>>摘要：The objective of this research is to investigate how the quantity of laminate layers impacts the Ramie-Eglass fiber hybrid composite utilized in the Jaloe Kayoh material, specifically concerning mechanical properties such as tensile strength and fiexural properties. In this research, the authors conducted tensile and fiexural testing on composites with varying quantities of laminate layers. The research findings indicate that incorporating a laminate layer into the hybrid composite positively affects its mechanical properties. The composites with 5 laminate layers had the maximum tensile strength, measuring approximately 59.79 MPa, and the highest tensile modulus, measuring around 3.15 GPa. The results suggest that adding a suitable number of laminate layers can enhance the composite's resistance to tensile stress and preserve its structural stiffness. Furthermore, the composite consisting of 6 laminate layers demonstrated the largest elongation at break, measuring at 2.04%. This result suggests that the material has a commendable ability to withstand strain before reaching its breaking point. For fiexural properties, the configuration with 3 layers of lamina shows the most optimal results with fiexural strength of around 161.11 MPa, fiexural strain of around 0.021, and fiexural modulus of around 3.47 GPa. Therefore, this configuration is recommended as the most optimal to withstand fiexural stress on Jaloe Kayoh. This study offers valuable insights into the correlation between the quantity of laminate layers and the mechanical properties of Ramie-Eglass fiber hybrid composites. These insights can be utilized to create advanced composite materials for Jaloe Kayoh boats.
Jihadul QahharMohd. lqbalAmir Zaki MubarakLaxman B. Abhang...
55-64页
查看更多>>摘要：Machining processes on hybrid composite materials involve activities such as surface cutting, hole drilling and other cutting processes to achieve final shape and dimension of the composite product. There were several unexpected situations during the process, such as ununiform vibrations due to inconsistent of natural fiber structures and nonideal cutting conditions lead to progressive tool wear and low quality of the cutting surface. In this study, an experimental approach was conducted on the milling process of polyester matrix-based composites reinforced with abaca and glass fibers, produced through the press molding process. The milling process was utilized by a 10 mm diameter 4-flute carbide end mill cutter with a 45-degree helix angle. The study aimed to investigate the influence of cutting conditions (spindle speed, feed, and depth of cut) on vibration during the milling process of abaca-glass fiber composites. Three levels of each cutting parameters were determined based on cutting tool working capabilities, i.e. the spindle speed = 2000, 3000 and 5000 rpm, the feed = 0.004,0.007 and 0.10 mm/tooth, and depth of cut = 1,1.5 and 2 mm. The Design of Experiment (DOE) was constructed by Box-Behnken technique of Response Surface Methodology. The down milling process were conducted for all scenario of DOE, and the vibration was measured using a digital accelerometer. The results of the study indicated that vibration increased with the increase of spindle speed, feed, and depth of cut. The results show that the maximum vibration value (0.0206 m/s~2) was obtained at a spindle speed of 5000 rpm with a feed of 0.07 mm/tooth and a depth of cut 2 mm. Meanwhile, the minimum vibration value (0.0143 m/s~2) was obtained at the spindle speed 2000 rpm, feed 0.04 mm/tooth and depth of cut 1.5 mm.
Saad Saleh AlghamdiRajkamal BaluNamita Roy ChoudhuryNaba Kumar Dutta...
65-70页
查看更多>>摘要：Amongst various strategies to mitigate the environmental impact of non-degradable polymers, the integration of Cork with fossil fuel-derived Nylon is considered an attractive option to develop a lightweight, strong composite. To optimize the integration of these materials for processing as 3D printed structures requires the exploration of functional compatibilizers to enhance the homogeneity and 3D printability of the Nylon-Cork composite. In this paper, Nylon-12 (PA-12) was mixed with cork in varying melted compositions using one coupling agent/stabilizer/compatibilizer, namely: 3-aminopropyl triethoxysilane (APTS), to improve the interfacial bond between the components and amenability for 3D printed composite structures. This paper examines the characteristics of this composite using scanning electron microscope (SEM), rheology experiments and differential scanning calorimetry (DSC). These findings are used to understand and explain the ensuing 3D printed characteristics using the APTS compatibilizer and Nylon-Cork ratios. This work is expected to be critical for developing low-density engineering products using PA-12-Cork composites and for sustainable processing, using 3D printing technologies.
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