Malaysian Journal on Composites Science and Manufacturing

Numerical Investigation of Injection Pressure Effect on the Performance and Emission of a Diesel Engine Fueled with Butanol-Diesel Blends

2024-02-21T08:19:47+07:00

Globally, fossil-based resources are becoming increasingly scarce as the demand for energy from power-producing systems rises. Diesel engines are a popular and efficient source of electricity, but different national and international organizations have imposed limits on diesel emissions. Reducing emissions and boosting performance are typical operations in diesel engines. ANSYS FORTE code was used to generate a thorough numerical configuration. Analyses were conducted on a single-cylinder, four-stroke, direct-injection diesel Cummins N-14 test engine setup running on a 40 percent butanol-diesel blend with injection pressure ranging from 400 bar to 1600 bar at constant speed conditions to determine its performance metrics (i.e. Thermal Efficiency & Specific Fuel Consumption), combustion attributes (i.e. In-cylinder Pressure, In-cylinder Temperature & Apparent Heat Release Rate), and emissions characteristics (i.e. CO emission, Nox emission & Soot emission). In general, as injection pressure was raised, thermal efficiency, CO emissions, and soot emissions all improved, while in-cylinder temperature, in-cylinder pressure & NOx emissions rose progressively. For instance, for 1400 bar fuel injection pressure, maximum in-cylinder pressure and in-cylinder temperature were found, around 18.6 bar and 1650 K, respectively, whereas injection started at a 22-degree crank angle before top dead center (bTDC). The optimal injection pressure for internal combustion engines was determined by considering both emissions and performance. The results indicated that an injection pressure near 800 bar led to the following outcomes: an in-cylinder temperature of approximately 1520 K, an in-cylinder pressure of around 17.5 bar, a thermal efficiency of 32.50%, and a specific fuel consumption of approximately 292 g/KW-h. Additionally, implementing a 90%-10% split injection method with equal crank angle duration (CAD) resulted in an average reduction of 4-6% in NOx emissions.

Effect of Metal Filler on the Welded Joint of X70 Steel Joined to Duplex Stainless Steel by Gas Arc Welding

2025-02-07T12:22:38+07:00

This study investigates the effects of using two different metal fillers on the microstructure, corrosion resistance, and mechanical properties of a duplex stainless steel and X70 steel welded joint, performed using the Gas Tungsten Arc Welding (GTAW) process. The electrodes employed were ER2209 and ER70S. The research aims to assess the feasibility of welding dissimilar steels with these two electrodes. Three weld passes were conducted using the different electrodes, followed by characterization of the welded joint's microstructure and evaluation of its mechanical properties. The primary characterization techniques included optical microscopy, scanning electron microscopy, Electron Backscatter Diffraction (EBSD), corrosion testing, Vickers microhardness, and tensile testing. The welded joint exhibited no visible defects, and using two electrodes increased the hardness, particularly in the fusion zone, where it reached 290 HV. Microscopic analysis revealed a solidification microstructure in the fusion zone. The welded joint demonstrated intermediate corrosion resistance between the two base steels (duplex stainless steel and X70). At the same time, its tensile strength was also intermediate, achieving more than 96% of the nominal tensile strength of duplex stainless steel. This approach of bonding dissimilar steels offers a potential solution for substituting one steel type with another in automotive structures, enhancing their resistance and reducing production costs.

Preparation of Antifouling Composite Coating for Rubber. Part 1: Manufacturing and Laboratory Testing

2025-01-22T12:48:03+07:00

This article introduces results of investigations on Cu₂O concentration on release rate of antifouling composite coating for rubber, effects of fineness on ability to release Cu₂O of paint (fineness of paint increases, Cu₂O release speed of composite coating decreases), effects of period from composite coating preparation to start testing on ability of Cu₂O release. Besides, effects of anti-UV additive on ability of composite coating to withstand from UV-thermo-humidity complex was also investigated. Results show that Cu₂O concentration is 25 weight percent (wt. %), fineness of paint is 75-80 µm are suitable, period from composite coating preparation to time for being used is about 5 days for the best antifouling grade while ensuring mechanical properties of composite coating. Anti-UV additive of 1 wt. % is suitable for antifouling composite coating for rubber.

Design and Fabrication of a Quick Action Medicine Dispensary

2024-06-14T03:13:09+07:00

One of the major concerns in the medication process is ensuring that patients take the right medicine at the right time. This issue often necessitates additional assistance, especially for patients who need to take multiple medications multiple times a day, as it can be challenging to remember and manage all medications efficiently. Extensive research has been conducted on developing automated medicine dispensaries to aid patients in this process. However, most existing solutions are either theoretical design concepts or limited to dispensing medicines in batches only. This research aimed to design and fabricate an automated and universal medicine dispensary that addresses the challenges of accessibility and the complexities of scheduled medication intake. This dispensary also provides the capability to dispense medicines both in batches and as single units, according to user requirements. A comprehensive design concept was developed, incorporating essential features such as medicine storage, a user interface, a dispensing mechanism, and a timer system. The prototype was constructed using polyvinyl chloride (PVC) and polylactic acid (PLA), and its functionality was evaluated. The evaluation demonstrated that the automated dispensary could store multiple types of medicines. It featured a compact and user-friendly interface, an accurate alarm system for reminding patients of their scheduled medication times, and a precise dispensing mechanism capable of dispensing medicines discretely and in batches. This automated medicine dispensary, leveraging composite materials like PVC and PLA, has the potential to streamline medication intake processes, enhance healthcare services and revolutionize next-generation medicine.

Taguchi Method-Based Optimization of Single-Pass Abrasive Waterjet Cutting of Thick Aluminium

2025-04-21T07:13:48+07:00

Cutting force attenuation in AWJ induces surface defects (high Ra, large theta) in metals and delamination in composites, especially in thick sections that limiting industrial adoption and requiring post-processing. A robust Taguchi experimental design was employed to optimize AWJ cutting parameters to minimize these issues when cutting thick aluminium blocks. An L8 orthogonal array with three factors; waterjet pressure (WP), stand-off distance (SOD), and traverse speed (TS), each at two levels, was used and analyzed via Minitab software. Other parameters remained constant: nozzle diameter (1.0 mm), abrasive size (80 mesh), and abrasive flow rate (0.3 kg/min). Traverse speed was found to be the most critical factor affecting Ra and theta, though waterjet pressure and stand-off distance also had significant impacts. The optimal parameters, higher waterjet pressure (315 MPa), lower traverse speed (38 mm/min), and lower stand-off distance (3 mm), yielded the best results for both Ra (4.2 µm) and theta (1.24°). In conclusion, the interaction of optimized AWJ parameters enhances kinetic energy and momentum transfer, improving material removal efficiency and cutting surface quality. The study systematically evaluates critical abrasive waterjet parameters to optimize cutting strategies, demonstrating applicability for thick aluminium and diverse material types.

Effect of Sodium Chloride-Assisted Heat Treatment on Virgin and Recycled PLA Filaments in FDM 3D Printing

2025-04-21T13:41:13+07:00

Polylactic acid (PLA) is widely employed in Fused Deposition Modeling (FDM) owing to its biodegradability and ease of processing. Nonetheless, both virgin and recycled forms of PLA exhibit susceptibility to mechanical degradation, particularly under thermal stress. This study investigates the influence of sodium chloride-assisted post-processing heat treatment on the tensile properties of virgin PLA (vPLA), commercial recycled PLA (c-rPLA), and self-extruded recycled PLA (se-rPLA). Sodium chloride, used in the powder bed, helps regulate heat distribution during thermal treatment, improving tensile strength by reducing thermal degradation. Specimens were subjected to thermal treatment in a sodium chloride powder bed at 70°C, 85°C, and 100°C for 90 minutes. Tensile testing, conducted in accordance with ASTM D638, revealed strength improvements ranging from 3–6% for vPLA and 14–18% for c-rPLA. However, a tensile strength reduction of approximately 36% was observed in se-rPLA after heat treatment at 85°C, likely due to thermal sensitivity or material degradation. These findings suggest that while heat treatment can enhance the performance of commercial recycled and virgin PLA, its effectiveness for self-extruded PLA depends heavily on prior processing conditions. The study highlights the importance of carefully tailoring thermal post-processing protocols to the specific characteristics of recycled materials to support their use in sustainable 3D printing.

Multi-Criteria Decision Analysis for Optimal Material Selection in Unmanned Aerial Vehicle Manufacturing

2025-04-11T16:26:14+07:00

Unmanned Aerial Vehicles or UAVs were pilotless aircraft or aircraft with minimum human interaction. UAVs material and structure were critical aspects to consider throughout the development phase. UAVs were utilized in both the military and the civilian sector. However, because of this diversity of uses, their materials and structure differed due to the requirements and resilience needed for those uses. Due to the different materials used in the other development of UAVs, this study aimed to study the appropriate structure material for the development of UAVs. Moreover, this study investigated the process of preparing the body structure of the selected material from developed UAVs particularly for military specifications. Additionally, this study analyzed the best approach that was used to reduce the maximum take-off weight. This study focused on the best structure from the successful product of UAVs from the selected company. This case study was performed to investigate what had been practiced and for further analysis while analytical hierarchy process (AHP) and quality function deployment (QFD) were used as research methods to perform the multi-criteria decision analysis. Carbon fiber was selected as suitable material for wing and propellor while fiberglass composite was identified as suitable material for tail and body of UAVs. This study provided a strong basis for future UAV development, this all-encompassing strategy sought to create an organized framework for decision-making that synchronized technical specifications with operational and customer objectives.

Mechanical Performance of Recycled Polypropylene Composites Reinforced with Activated Carbon-Treated Clay as Concrete Aggregates

2025-04-22T09:45:14+07:00

The growing concern over plastic waste and the depletion of natural aggregates has spurred interest in sustainable construction materials. This study examines the mechanical and morphological performance of recycled polypropylene (rPP) composites reinforced with activated carbon (AC)-treated clay for use as lightweight concrete aggregates. The novelty lies in the hybrid filler system combining clay and AC within a recycled polymer matrix; an approach rarely explored for structural concrete applications. Composites were fabricated using a single-screw extruder at 185°C and 50 rpm, incorporating AC at 1, 3, 7, and 15 wt%. Mechanical testing revealed that 3 wt% AC achieved the highest tensile strength due to enhanced filler dispersion and interfacial bonding, while 15 wt% AC increased stiffness but reduced elongation due to agglomeration and brittleness. The highest yield strength at 7 wt% AC suggests a percolation threshold effect, improving load transfer efficiency. FESEM and EDX analyses confirmed better filler distribution and matrix-filler interaction at lower AC contents, aligning with mechanical results. These findings highlight rPP/clay/AC composites as eco-friendly, lightweight concrete aggregate alternatives with a balance of strength, stiffness, and flexibility. This study underscores the environmental benefits of repurposing plastic and carbon-based waste while recommending further investigation into their long-term durability and real-world performance.

Parametric Study and Characterization of Nitrogen-Doped Carbon Quantum Dots Synthesized via Hydrothermal Method

2025-04-22T16:23:52+07:00

Carbon quantum dots (CQDs) are zero-dimensional nanomaterials known for their chemical stability, water dispersibility, low cytotoxicity, small size, biocompatibility, and photoluminescence. This study reports the synthesis of nitrogen-doped CQDs (N-CQDs) using urea and citric acid derived from calamansi lime via a simplified hydrothermal method. A 2³ full factorial Design of Experiments (DOE) optimized synthesis parameters: temperature, reaction time, and precursor ratio. Optimal conditions were 140°C, 2 hours, and a 1:1 precursor ratio. The resulting N-CQDs exhibited strong photoluminescence, excellent colloidal stability, and particle sizes ranging from 5 to 10 nm. Tauc plot analysis indicated bandgap energies up to 5.81 eV, influenced by particle size and quantum confinement. UV-Vis and FTIR spectroscopy confirmed the absorption behavior and the presence of nitrogen and oxygen functional groups, respectively, while photoluminescence measurements showed intense emission. FESEM, TEM, and EDX analyses revealed uniform spherical morphology and confirmed successful nitrogen doping. The tunable surface chemistry and optical properties of N-CQDs make them promising for bioimaging, sensing, and optoelectronics applications. The sustainable, cost-effective hydrothermal synthesis method supports scalable production for use as functional fillers in nanocomposites.

Production of Porous Copper via Uniaxial Compaction Assisted by Potassium Chloride as a Space Holder

2025-04-22T09:58:07+07:00

Porous metal fabrication has garnered considerable attention for its cost-effectiveness, lightweight properties, and desirable characteristics such as mechanical strength, thermal management, acoustic insulation, and fluid permeability, making it valuable across industries like automotive, biomedical, aerospace, and electronics. Among these, porous copper stands out for applications like heat sinks in portable electronic devices due to its high specific surface area and excellent permeability. However, the challenge lies in achieving precise control over porosity and mechanical properties. This study explores the fabrication of porous copper using powder metallurgy, employing uniaxial compaction and potassium chloride (KCl) as a space holder. KCl was chosen for its chemical inertness and efficient dissolution properties. Copper-KCl mixtures with KCl content ranging from 10% to 30% were compacted at pressures between 9.81 MPa and 19.61 MPa, sintered at 700°C under an argon atmosphere, and subjected to a dissolution process at 50°C for 5 hours. Porosity was determined using a gravimetric method based on Archimedes’ principle, while X-ray Fluorescence (XRF) analysis assessed the efficiency of KCl removal. Uniaxial compression testing revealed the influence of porosity and compaction pressure on the mechanical strength of the samples. The findings highlight the potential of tailored porous copper for lightweight, high-performance applications requiring controlled thermal and mechanical properties.

A Study of Fracture Toughness Towards Polypropylene Nanoclay Nanocomposites with Different Bamboo Fiber Loading

2025-04-28T07:57:10+07:00

The development of sustainable, high-performance materials is crucial to meet the demands for eco-friendly and durable composites in various industries. Polypropylene nanoclay composites reinforced with natural fibres, such as bamboo, offer a promising alternative due to their improved mechanical properties and environmental benefits. However, the fracture toughness of these polypropylene nanoclay composites with varying bamboo fibre loadings remains insufficiently studied, particularly in terms of how different fibre concentrations impact the material's resistance to crack propagation and overall mechanical integrity under stress. Therefore, this paper was published to elucidate the findings of fracture toughness analysis of polypropylene nanoclay bamboo fibre nanocomposite that consist of 0 wt.%, 3 wt.% and 6 wt.% of bamboo fibre loadings. This research aims to systematically investigate how different bamboo fibre loadings affect the fracture toughness of polypropylene nanoclay nanocomposites. The study will assess the composite’s behaviour under fracture and determine the optimal fibre loading for maximizing fracture toughness while maintaining lightweight and eco-friendly characteristics. The sample was moulded by an injection moulding procedure, with compounded samples of polypropylene, bamboo fibre, polypropylene-graft-maleic anhydride (compatibilizer), and nano clay. The optimal injection moulding temperature for the sample was determined using Differential Scanning Calorimetry and Thermogravimetric Analysis. The Mode 1 plane strain fracture toughness was evaluated using the Linear Elastic Fracture Mechanics approach in accordance with ASTM D5045. As for the results, the composite with 6 wt.% bamboo fibre has the highest value of the average fracture toughness with 62.9743 MPa.m^1/2, as compared with sample of 3 wt.% bamboo fibre, which is 59.6709 MPa.m^1/2. Meanwhile, the sample without the presence of bamboo fibre has lowest average fracture toughness at 43.260 MPa.m^1/2. In conclusion, the bamboo fibre has proven its potential to be a promising reinforcing agent, and it can be used in any suitable applications, such as automotive components, building materials and packaging solutions.

Composite Hydraulic Integration: A New Step Toward Lightweight Hydraulic Robots

2025-04-28T08:01:04+07:00

Normally, the use of hydraulics in humanoid robots is limited due to their design complexity, heavy weight, and high cost. This paper presents a new methodology for developing hydraulic integrated robotics system with lightweight, high strength, shorter production time and lower cost. This is achieved by combining the additive manufacturing of thermoplastic polymers and the simple forming of strong random fiber composites. A new methodology for fabrication of complex hydraulic integrated parts is explained in detail. The robotic arm of the humanoid hydraulic robot HYDROïD is chosen for implementing the new technique, specifically, the elbow lower part. A theoretical study for different possible 3D printing and reinforcement materials is presented. Then, an optimization method is presented to select the 3D-printed polymer material, the composite, the adequate sizes, and dimensions of the new arm part. Experimental validation and testing of the new part are presented. Moreover, PID gain scheduling controller (PID-GSC) is applied on the robotic arm during validation. The achieved results have shown that the new technique has led to significant weight reduction in the arm components to about 60% of the initial weight with a pressure tolerance of 150 bar. In addition, position tracking has been achieved successfully. Hence, the new attained solution has proved its worthiness with much lower cost and simple fabrication procedures.

Enhancement of Water Quality Parameters with Microplastics via Electrocoagulation

2025-04-28T08:02:30+07:00

Microplastics are classified into two groups: any plastic pieces or particles already 5.0 mm in size or smaller. Primary microplastics include clothing microfibers, microbeads, and plastic pellets (nurdles), and the other is secondary microplastics, which form when bigger plastic materials degrade (break down) in the environment due to natural weathering processes. Secondary microplastics originated from drinking bottles, fishing nets, plastic bags, microwave containers, tea bags, and tyres. Both varieties persist at high environmental levels, particularly in aquatic and marine habitats. A water sample was taken from the Tampoi River near Universiti Teknologi MARA Campus Dengkil. In-situ and laboratory testing were analyzed to characterize the water sample. The parameters conducted for the evaluation were pH value, turbidity, total suspended solids, ammonia-nitrogen (NH₃-N), biochemical oxygen demand (BOD), chemical oxygen demand (COD), nitrite-nitrogen (NO₂-N), nitrate-nitrogen (NO₃-N) and enumeration of bacteria (Escherichia coli). During the electrocoagulation treatment, two types of polypropylene microplastic – fine polypropylene and coarse polypropylene were inserted in the samples. Later, the Fourier Transform Infrared (FTIR) was done for the polymer before and after treatment. The changes in the chemical structure of each polymer in FTIR demonstrated the changes in peak after the incubation periods: the chemical O-H bond and C=C bond have been detected for both types of polypropylenes.

Representative Volume Element in Photopolymerization Additive Manufacturing Techniques for Mold Production: A Comprehensive Structured Review

2025-04-28T08:03:38+07:00

In recent years, the use of Representative Volume Elements (RVE) in photopolymerization additive manufacturing (AM) for mold production has attracted significant attention for its potential to enhance material performance and structural reliability. This systematic literature review (SLR) provides a structured analysis of recent developments in RVE applications within photopolymerization techniques. It focuses on their effectiveness in addressing the challenges of dimensional precision, mechanical strength, and thermal stability in AM molds. The review addresses the need for a consolidated understanding of RVE’s role in optimizing photopolymerization processes to achieve superior mold quality for industrial applications. A comprehensive search was performed following the PRISMA guidelines across established databases, for instance, Scopus as well as Web of Science (WoS), emphasizing research published from the year 2022 to 2024

. A total of 26 relevant articles were analyzed, categorizing findings into three key themes: (1) hybrid and multi-material manufacturing techniques, (2) material-specific AM and characterization, and (3) applications and performance enhancements in AM. Results indicate that RVE integration in photopolymerization AM techniques can improve mold properties by up to 30%, with advancements in fiber orientation and controlled curing processes contributing significantly to performance. This review highlights RVE’s critical role in advancing photopolymerization AM for mold production and suggests further research into standardized RVE methodologies for scalable and high-performance mold applications. The findings offer valuable insights for industries seeking reliable and efficient manufacturing solutions through AM innovations.

Relationship of Additive Dosages to Polyvinylidene Fluoride (PVDF) Ultrafiltration: Dye Rejection Study

2025-04-28T08:04:50+07:00

Ultrafiltration membrane is often used in wastewater treatment plants to remove dyes and other contaminations. This study aims to improve the properties and methylene blue rejection efficiency of the polyvinylidene fluoride (PVDF) ultrafiltration (UF) membranes by introducing copper acetate monohydrate/magnesium sulphate (CuMgNTs) at different loading dosages. The flat sheet membranes were successfully fabricated using the phase inversion method. The physicochemical properties of membranes were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) and Fourier transform infrared spectroscopy (FT-IR). The pure water flux tests showed that the M3 membrane with 3wt.% of CuMgNTs loading exhibits the highest pure water flux of 47 L/m²h. For methylene blue rejection efficiency M3 membrane possessed the highest rejection efficiency up to 94%. The M3 membrane performance showed an increase in pure water flux and methylene blue dye rejection up to 224% and 74%, respectively, compared to pristine PVDF membrane. Therefore, it can conclude that 3wt.% of CuMgNTs is the optimum loading for PVDF UF membrane in improving its permeability towards pure water and performance to reject methylene blue dyes.

Rare Earth Elements Adsorption Using Electrospun Nanofiber of Blended Nylon 6-6 and Choline Ionic Liquid from Aqueous Solution

2025-04-28T08:06:00+07:00

Rare earth elements are among the critical components that are essential to many sectors, especially the production of advanced products. These rare earth elements are now heavily dependent upon by large worldwide enterprises. There have been accounts of separating rare earth elements using diverse adsorbents, including functional polymer compounds, resins, biomaterials, and inorganic nanoparticles. Nevertheless, these materials often encounter constraints related to low adsorption capacity or the risk of causing secondary pollution. This study applied the electrospinning method for making and characterizing nanofibers and enhanced the adsorption of rare earth elements from aqueous solution with nylon 6,6 polymer and choline oleate mix. When compared to pure nylon 6,6 nanofibers, the electrospun nanofibers showed altered morphological characteristics, pore size, and diameter. The effective integration of choline oleate was validated by FTIR spectra, which showed that the functional groups in pure and blended nanofibers were comparable. Adsorption tests revealed that the mixed nanofiber exhibited a higher capacity for adsorbing rare earth elements compared to the pure nanofiber, reaching 295.66 mg/g for the mixed nanofiber and 16.17 mg/g after 24 hours. This improvement was ascribed to the blending-induced addition of functional groups, which promoted stable chelate connections between surface groups and REE ions. The study underscores the potential of choline oleate-blended nylon 6,6 nanofibers as effective adsorbents for REEs, emphasizing the importance of surface modification for improved adsorption performance.

Injection Moulding Parameters Effect on Fracture Toughness of Polypropylene Nanocomposite Gigantochloa Scortechinii Using Taguchi Method

2025-04-28T08:07:17+07:00

This paper presents an experimental study about injection moulding parameters effect on fracture toughness of polypropylene-nanoclay-gigantochloa-scortechinii nanocomposites with 0 wt.%, 3 wt.%, and 6 wt.% of bamboo fibre content. The selected parameters were melt temperature, packing pressure, screw speed and filling time. The composite samples were injection moulded from a material consisting of polypropylene, bamboo fibres, compatibilizer, and nanoclay. Linear Elastic Fracture Mechanics method according to ASTM D5045 was used to evaluate the fracture toughness. The experimental design was made by adopting the Taguchi Method Orthogonal Array. Analysis of variance was used to determine the most contributing parameters and the plot of main effect diagrams were used to define the optimum factor values. The results showed that the composite with 6 wt.% bamboo fibres had the highest KIc value of 18.188 MPa.m^1/2, while the nanocomposite without bamboo fibres had the lowest KIc value, 11.693 MPa.m^1/2. It was found that the fracture toughness increased with the addtion of bamboo fibre. As for the samples made of 6 wt.%, the melting temperature was the most influential factor affecting the fracture toughness, but for samples made of 3 wt.% the packing pressure is the decisive factor. The combination of 175°C melt temperature, 50% packing pressure, 40% screw speed and 2 seconds filling time results in the sample with 3 wt.%, bamboo fibre content. The combination of 170°C melt temperature, 45% packing pressure, 30% screw speed and 2 seconds filling time, were the optimum values for the 6 wt.%, bamboo fibre content sample that produced the highest fracture toughness for this formulation. The knowledge from this research was useful for manufacturing industries that using injection molding process to produce their product, by using this new type of material. On top of that, the use of organic and natural materials such as bamboo fibres can acellerate the efforts in reducing the environmental footprint.

Mechanical Strength and Degree of Polymerization of Oil-paper Non-wood Kenaf Bast Fiber as New Transformer Insulation Presspaper

2025-04-28T08:08:26+07:00

Utilization of Rice Husk Fiber Blended Recycled Polyethylene Terephthalate for Manufacturing RHF/R-PET Polymer Composites

2025-04-28T08:09:26+07:00

In response to the growing global awareness of the environmental crisis, a natural fiber-blended polyethylene material is being developed for the production of polymer composites. This research focuses on harnessing abundant waste materials such as Rice Husk Fiber (RHF) and Recycled Polyethylene Terephthalate (R-PET) in Malaysia to create RHF/R-PET polymer composites. The main goal of this study is to identify and characterize the optimal composition of RHF/PET polymer composites suitable for deck panel applications. The research investigates various composition ratios of RHF fibers, ranging from 5 to 20 wt/w% when blended with R-PET sourced from recycled bottles produced at Angkasa Kowaris Plastics Sdn Bhd. This study holds significant importance in the development of an environmentally friendly polymer composite material, utilizing abundant natural resources approaching RHF fibers found in Malaysia. The study includes physical and mechanical testing of samples with different RHF fiber composition ratios. The findings reveal that the ideal combination for producing polymer composites for deck panels is achieved at a 20 wt/wt% ratio of RHF/R-PET. This composition provides good matrix bonding between RHF and R-PET with density and porosity at 1.043 g/cm3 and 0.076%, respectively. It also exhibits a maximum tensile strength of 12.53 MPa, exerting a force at 138.90 N with a maximum stress of 14.8 N/mm2. Additionally, 20 wt/wt% gives a higher Young’s modulus value at 12.12 MPa. For bending strength 20 wt/wt% was achieved at 19.78 N with a maximum stress of 10.45 MPa. The incorporation of RHF fibers in fiber-reinforced composite applications offers economic benefits due to their renewability, biodegradability, and cost-effectiveness compared to manufactured fibers. This approach has the potential to contribute significantly to Malaysia's economy by providing a waste material alternative to raw materials while maximizing the utilization of RHF fibers and R-PET waste resources.

Effect of Water Content in Raw Material Mixtures on the Proximate, Physical, and Mechanical Properties of Coconut Shell Charcoal Briquettes Produced with a Screw Extruder Machine

2025-05-02T10:47:31+07:00

Coconut shell charcoal briquettes offer a green and productive energy option. However, past studies have looked at single factors without exploring how water levels in raw material mixes affect briquette performance. This research aims to fill this gap by looking at how different water contents in the raw material mixture (44.9%, 46.5%, 49%, and 52.5% for Specimens A, B, C, and D) impact the quality of briquettes made with a screw extruder machine. To produce briquettes, the process involves several steps: preparing coconut shell charcoal powder, mixing this powder with a binder (5% tapioca), adjusting water content to reach the desired levels, blending the mixture thoroughly, forming the mixture using a screw extruder machine, and drying the resulting briquettes. The study used established techniques to assess proximate properties, physical characteristics, and mechanical performance (compressive strength and friability). The findings demonstrate that Specimen C, displaying a water content of 49%, showed the most favourable overall performance. The data indicates the highest fixed carbon content at 71.80%, a calorific value of 7,102 Cal/g, and a density of 0.57 g/cm³ while also showing the minimum friability at 9.43%. Conversely, Specimen D, exhibiting the highest water content at 52.5%, showed the lowest friability at 40.19% and a compressive strength of 14.58 kg/cm². The results of this study indicate that the water content of 49% significantly improves briquette quality, achieving a balance between structural integrity and combustion efficiency. This study offers essential findings on enhancing briquette production processes, creating high-quality briquettes for domestic and international markets, and supporting the sustainable use of coconut shell waste.

Review of Predictions of Impact Performances and Damages of Fiber Reinforced Composite using Machine Learning Approaches

2025-05-02T10:48:50+07:00

Fiber-reinforced composites (FRCs) offer high specific mechanical properties like-exceptional strength, lightweight properties, and versatility, but their susceptibility to impact damage poses a significant challenge. Characterizing these while connecting processing methods, microstructure, and environmental factors to impact response has seen limited success through conventional modeling. But with increasing computational power and availability of data, machine learning techniques present opportunities in this domain enabling accurate prediction and robust monitoring of impact performance and damage.

This review paper provides a comprehensive examination of the evolving landscape in predicting impact performances and damages of FRCs to optimize composites’ design through the lens of different supervised, unsupervised, blended, deep transfer learning and alternative approaches

highlighting their strengths, limitations, and suitability for specific tasks. Methods encompassing artificial neural networks (ANNs), support vector machines (SVMs), and convolutional neural networks (CNNs) have exhibited promise in predicting performance and damage parameters respectively. Each section critically evaluates the strengths, limitations, and contributions of these approaches, providing a holistic view of their effectiveness.

The Effects Strength & Density of Autoclaved Aerated Concrete Containing Semiconductor Electronic Molding Resin Waste (AAC-SEMRW) on Partition Panel Application

2025-05-02T10:50:37+07:00

Semiconductor Electronic Molding Resin Waste (SEMRW) a byproduct of IC package manufacturing, is widely utilized in the electronics industry. However, recycling this material in an efficient and sustainable manner remains critical, especially for promoting eco-friendly practices in construction. This study focuses on repurposing SEMRW autoclaved aerated concrete (AAC) for partition panel applications. Resin waste obtained from STMicroengineering Sdn Bhd was finely ground to a particle size of 0.1 ± 0.01 mm and incorporated into the AAC mixture in varying percentages—0%, 5%, 10%, 15%, 20%, 25%, and 30% containing with standard amounts of cement, quartz sand, water, and a 3% aluminum paste. The prepared mixtures were molded and curing into autoclaved machine for 4 hours. Experimental results indicated a reduction in both water absorption and pore formation as SEMRW content increased. Microstructural analysis using Scanning Electron Microscopy (SEM) revealed a more compact structure with higher RW proportions. The AAC-SEMRW composition containing 20% resin waste achieved the highest compressive strength values, with 7.29 MPa after 8 hours of curing in Autoclaved Machine. Furthermore, this composition exhibited the greatest residual compressive strength (8.22%) when exposed to elevated temperatures. Based on these findings, the 20% SEMRW formulation is identified as the optimal mixture, offering improvements in water absorption, compressive strength, and thermal resistance. This research contributes to sustainable waste management, provides an innovative green construction material, and enhances the performance of AAC for partition panel applications, reflecting a significant advancement in construction technology.