Journal of Advanced Research in Micro and Nano Engineering

Wear Behaviour of Nickel Coatings Reinforced by Recycled Quarry Dust: Influence of Current Density

Intan Sharhida Othman — 2024-12-05

Nickel coatings incorporated with quarry dust were synthesized through direct current electrodeposition from a nickel Watt’s bath. The study explored the effects of varying current densities on the surface morphology and wear behaviour of the nickel-quarry dust (Ni-QD) composite coatings deposited on a high-speed steel (HSS) substrate. Quarry dust was chosen as a reinforcement material due to its high silica and alumina content, which enhance the properties of the coating. To achieve finer particle size, the quarry dust was subjected to ball milling before electrodeposition. The study tested a range of current densities from 2 to 8 A/dm², as different current densities produce different results. The composite coatings were characterized using a Scanning Electron Microscope (SEM) and their wear resistance was evaluated through pin-on-disk test. The results indicated that increasing the current density enhanced the wear resistance of the coatings. Coatings produced at high current densities displayed a colony-like structure, demonstrating the impact of deposition conditions on colony size relative to current density. Ni-QD composite coatings created at 6 and 8 A/dm² resulted in smoother and narrower wear scars with minimal scratching, attributed to the low surface roughness of the coatings.

The Potential of Microalgae in Chitosan and Cellulose as Sustainable Materials for Edible Bioplastic Applications: A Review

Nur Nadiah Che Aziz — 2024-12-05

The demand for eco-friendly food packaging options with additional features to prolong shelf life has continuously increased since 1940. Bioplastic is gaining popularity as a viable replacement for plastics based on fossil fuels due to fluctuating oil prices. Therefore, technological innovation is required to resolve the issue. This study aimed to review the distinct characteristics of integrating chitosan and cellulose alongside exploring the capabilities of microalgae in bioplastic production. The potential techniques and applications for future development were also suggested. The unique growth yield of microalgae makes them a compelling option for producing bioplastics. Hence, utilizing microalgae for bioplastic production offers a significant opportunity to enhance moisture barrier capacity, alter the structural properties, and adjust the flow behaviour. Moreover, these materials can also serve as the key nanocomposites components in the food packaging industry. The potential for chitosan/cellulose/microalgae-based bioplastic and the key themes and obstacles for future research into these composites for bioplastic production were also reviewed.

Boiling Heat Transfer Coefficient of Hybrid Nanofluids with and without Surfactant

Muhamad Zuhairi Sulaiman — 2024-12-05

Experiments were carried out to investigate the effect of surfactants on the boiling heat transfer coefficient of hybrid water-based nanofluids. In the present work, both Al2O3- SiO2 and Al2O3-TiO2 hybrid nanofluids were prepared with a 75:25 composition ratio and concentration of 0.01 v/v%, mixed with SDS surfactant of 40 ppm and prepared using ultrasonic process. It was found that Al2O3-SiO2 and Al2O3-TiO2 hybrid nanofluid enhance BHTC performance compared with distilled water, however, its performance will deteriorate gradually after 5 minutes of the experiment. Additional SDS in both Al2O3-SiO2-SDS/Water and Al2O3-TiO2-SDS/Water hybrid nanofluid will increase its BHTC performances up to 112.27% and 127.03% respectively compared with distilled water. Al2O3-SDS has better BHTC performance compared with Al2O3-SiO2 and Al2O3-TiO2 hybrid nanofluid which is 327.15% compared with distilled water.

Enhancing Thermal Conductivity of Water-Ethylene Glycol Mixtures: A Study on TiO2-Al2O3 Hybrid Nanofluids with Surfactants

Wajiha Tasnim Urmi — 2024-12-05

This analysis examines the thermal behaviour of 40% ethylene glycol-based TiO2-Al2O3 hybrid nanofluids by synthesizing them and assessing their thermal conductivity as a function of volume concentration and temperature. These hybrid nanofluids, emerging as a promising new class of advanced operating fluids, offer remarkable potential for enhancing heat transfer performance in various thermal engineering applications. Using a two-stage synthesis method, TiO2-Al2O3/40% ethylene glycol nanofluids were prepared across five distinct volume focuses (varying from 0.02% to 0.1%), incorporating Polyvinylpyrrolidone (PVP) as a stabilizing emulsifier. Precise thermal conductivity measurements were conducted over 30 °C to 80 °C, with incremental steps of 10 °C, ensuring comprehensive data collection. The investigation yielded significant findings, notably a substantial maximum thermal conductivity enhancement of 37.44%, observed at 80 °C with a 0.1% volume concentration, demonstrating pronounced sensitivity to elevated temperatures and concentrations. The strategic addition of PVP surfactant resulted in a remarkable 125% improvement in the nanofluid's stability period, although a maximum 5.33% reduction in thermal conductivity. Considering the inadequacy of existing predictive models to capture the observed data accurately, this study proposed developing a high-precision predictive model, achieving an impressive maximum deviation of less than 3%. The research concludes that these hybrid nanofluids, characterized by their exceptional stability and significantly enhanced thermal conductivity, hold immense potential to revolutionize heat transfer applications across various domains of practical thermal engineering. This breakthrough paves the way for developing more efficient, high-performance heat transfer systems, potentially catalysing energy efficiency and thermal management advancements across diverse industrial sectors.

Sustainable Waste Oils Polymer Doped with Titanium Dioxide as Ultraviolet Stabilizer

Anika Zafiah Mohd Rus — 2024-12-05

Waste oils for biopolymer conversion process namely as sustainable monomers with biodegradable properties that are prepared in a multi-stage synthesis route from vegetable oils. These sustainable monomers from virgin oil (VO) and waste oil (WO) were mixed with hardener to form virgin oil sustainable polymer (VOP) and waste oil sustainable polymer (WOP). VOP and WOP were left to cure at ambient temperature for at least 6 hours and removed from the mould. The steps were repeated to fabricate sustainable polymer composite (SPC) doped with different percentages of TiO2. The samples of biopolymer (BP) are based on VOP and WOP, while biopolymer composites (BPC) were based on TiO2 percentage. The thickness of the prepared sample is from 110 to 250 µm according to ASTM D1005-95. The study on the thermal stability property of these polymers in oven thermal exposure shows a significant stability of these polymer films which was determined by calculating the carbonyl index (CI) of polymer films. The VOP shows the leaststability upon thermal exposure which its molecular chains contain many reactive sites, thus providing more potential for degradation, resulting in lower thermal and bio-stability. Also, it is revealed that polymers are susceptible to photodegradation initiated by heat or UV light during processing or long-term use. Therefore, UV accelerated weathering test was conducted according to ASTM D 4587- Standard practice for fluorescent UV-condensation exposures of paint and related coatings. Furthermore, a tensile test was conducted to determine the strength and ductility of a material. The mechanical properties of polymer thin films were significantly reduced by UV irradiation exposure. As opposed to WOP, VOP gives better results for tensile strength and elongation at break.

Insight into Magnesium Doping on Morphology, Optical, and Electrical Properties of Cu2O Layer Synthesized by Electrodeposition Method

Mohd Zamzuri Mohamad Zain — 2024-12-05

Cu₂O stands out as a promising semiconductor material for solar energy conversion, primarily due to its exceptional light-absorbing qualities and its widespread availability. However, its efficiency is somewhat hindered by its relatively low carrier mobility and a limited absorption band for carriers. The introduction of magnesium (Mg) doping into Cu₂O has emerged as a potential means to enhance its morphology, optical characteristics, and electrical properties, making it an intriguing avenue for exploration. To fabricate the Mg-doped Cu₂O layers, an electrodeposition process was employed on an Indium Tin Oxide (ITO) substrate. The resulting films were then subjected to characterization using Field Emission Scanning Electron Microscopy (FESEM), Ultraviolet-Visible Spectroscopy (UV-Vis), and HALL Effect Measurement, focusing on their morphology, optical properties, and electrical behaviors. Notably, the concentration of magnesium played a significant role in shaping the properties of the Cu₂O layer. The fabrication process extended up to a dopant concentration of 0.3 M for both undoped Cu₂O and Mg-doped Cu₂O layers, leading to morphological alterations. Specifically, the grain size increased with varying dopant concentrations, but it became smaller and more compact after doping with 0.3 M Mg. The average absorbance of visible light for both undoped and Mg-doped Cu₂O layers fell within the range of 1~2 au. Intriguingly, a doping level of 0.3 M Mg led to the simultaneous achievement of high carrier mobility (29.98 cm²/Vs), low bulk carrier concentration (2.3.928 x 10²¹ cm^-3), and high resistivity (5.3 x 10^-5 ohm-cm) in the Cu₂O material. Additionally, Cu₂O/ITO thin films exhibiting rectifying characteristics were successfully fabricated, confirming the semiconductor nature of the deposited p-type Cu₂O layer. The primary objective of this study was to synthesize Cu₂O layers doped with varying concentrations of Mg and thoroughly characterize their morphology, optical attributes, and electrical behaviors through the electrodeposition method. The study findings and implications were extensively discussed.

Efficiency Enhancement of Parabolic through Solar Collector using ZnO/Water Nanofluid

Adnan Mohammed Hussien — 2024-12-05

In recent years, the increased demand for energy has contributed to an increase in the number of studies focusing on renewable energy sources. The empirical and theoretical efficiencies of a parabolic trough solar collector are investigated. Fluid includes 1% and 2% volume concentrations of ZnO/water nanofluid and mass flow rates of 0.15 to 0.25 to 0.35 kg/min. The experimental study took place over the course of three months (February, March and April) in Kirkuk, Iraq. The solar collector's thermal losses decreased as the flow rate increased, heat gain increased with sun intensity and the collector's actual and theoretical efficiencies all improved. The efficiency found in experiments was found to be 10% lower than that predicted by theory. At the greatest volumetric flow rate, using a nanofluid composed of 2% ZnO and water improves the performance of solar collectors by 9%.

Investigation of the Effect of Copper Nanoparticle Deposition on Low-Carbon Steel using Physical Vapor Deposition for Solar Cooling Application

Mohd Anas Mohd Sabri — 2024-12-05

The use of nanomaterials in solar cooling applications has gained significant attention in recent years. This study aimed to increase thermal conductivity by depositing copper nanoparticles (Cu-NP) on low-carbon steel using thermal evaporation and a physical vapor deposition (PVD) method. Low-carbon steel was selected as the substrate due to its wide use in thermal applications and strong absorption properties. The presence of Cu-NP on the surface was analysed using XRD and thermal characteristics of the thin layer were determined using Thermal Constant Analyzer (TCA) and Transient Plane Source (TPS) measurements. Results showed that the copper nanoparticle coating sample on the carbon steel substrate had better heat emission and absorption compared to the carbon steel alone. It also shows some improvement of around 1% in the thermal conductivity results. This study demonstrates the potential of using Cu-NP deposited on low-carbon steel as a promising material for solar thermal/cooling applications.

Characterization of Physical, Morphological and Mechanical Properties of Poly-Lactic Acid/Graphene (PLA/GNPs) Biopolymer Composites using Fused Deposition Modelling

Wan Sharuzi Wan Harun — 2024-12-05

A hybrid biopolymer composite consisting of Poly-Lactic Acid/Graphene Nanoplatelets (PLA/GNPs) was formulated using double planetary mixer (DPM) and processed into granules and utilized as the feedstock for additive manufacturing (AM) of structures using the Fused Deposition Modelling (FDM) technique. The study aimed to investigate the influence of different weight percentages (1%, 3% and 5%) of graphene nanoplatelets (GNPs) on the physical, morphological and mechanical properties of the printed test samples. Differential Scanning Calorimetry (DSC) revealed the temperature ranges for the glass transition temperature (Tg) and crystallinity temperature (Tc) to be 61–63 °C and 112–140 °C, respectively. Additionally, it was observed that the presence of graphene in the polymer matrix led to a decrease in the melting temperature (Tm), with the sample containing 1 wt% of GNPs displaying the highest melting point. Furthermore, the density of the biopolymer composite increased as the weight percentage of GNPs increased. Microscopic examination of the samples revealed the presence of voids, waves and interlayer gaps in all compositions containing GNPs. These conditions were likely caused by inadequate material preparation and inaccurate printing parameter settings. In terms of mechanical properties, the highest tensile modulus observed was 1.29 GPa with 5 wt% GNPs, the highest flexural modulus was 5.17 GPa with 5 wt% GNPs and the highest compressive modulus was 10.073 GPa with 3 wt% GNPs. These results may be attributed to low homogeneity during the mixing process.

Effect of Adding Al2O3 Ceramic in Wire Arc Additive Manufacturing 308LSi Stainless Steel

Mohd Hairizal Osman — 2024-12-05

Wire Arc Additive Manufacturing (WAAM) is a process that allows for efficient in-situ production of components or remanufacturing based on its capabilities to produce at a greater rate of deposition at a lower cost. However, WAAM components suffer from heat dissipation during the deposition process that causes the growth of coarse columnar grains resulting in poor mechanical properties that will limit industrial applications. Thus, this research investigates the role of introducing Al₂O₃ ceramic powder particle inoculants to the AWS A5.9 ER308LSi stainless steel wall structure to enhance the mechanical performance capabilities by refining the grain process. During deposition, the Al₂O₃ ceramic powder particle was manually added to each layer when the temperature drops to 150 degree celcius. A complete series of tensile testing was executed to bridge those knowledge gaps. WAAM walls were fabricated and the microstructure of the sample were analysed. The results revealed that the highest tensile strength of WAAM SS308LSi components recorded at 560 MPa in the deposition direction, which increased by 6% compared to the non-inoculated sample. The improvement was due to the success of grain refinement and heterogeneous nucleation. The study demonstrates the potential of the technique to improve the mechanical properties and microstructure during WAAM components fabrication or remanufacturing.