Mechanical property and prediction model for FDM-3D printed polylactic acid (PLA)

Fused deposition modeling (FDM) has been the preferred technology in 3D printing due to its ability to build functional complex geometry parts. The lack of the printing parameter information and prediction model that directly reflects towards 3D printed part's mechanical properties has been a barrier for the FDM 3D printer users to appraise the product's strength as a whole. In the present work, 27 tensile specimens with different parameter combinations were printed using a low-cost FDM 3D printer according to the ASTM standard to evaluate their tensile properties. Statistical analysis was performed using MINITAB to validate the experimental data and model development. The investigational outcomes reveal that ultimate tensile strength was primarily affected by infill density, whereby it increases with increasing infill density. Elastic modulus, fracture strain, and toughness were mainly affected by infill density and layer thickness. The ideal printing parameter for optimal tensile behavior was identified to be 0.3 mm layer height, 40° raster angle, and 80% infill density from the 9th combination. The tensile values obtained for the optimal printing parameter were 28.45150 MPa for ultimate tensile strength, 0.08012 mm/mm for fracture strain, 828.06000 MPa for elastic modulus, 20.19923 MPa for yield strength, and 1.72182 J/m3 for toughness. The statistical analysis further affirmed the optimum printing has a minimal deviation from the experimental response. Finally, a mathematical model is proposed for the tensile properties prediction

Progress in one-dimensional nanostructures

In recent years, the globe has been confronted with a large number of challenges related to power supplies, atmospheric pollution, and greater energy demand. Therefore, renewable energy sources or green energy have gained a great interest among researchers to deal with the aforementioned challenges. Scientists have sought to address these obstacles by developing groundbreaking functional technologies using nanomaterials. One-dimensional (1D) nanostructures, such as nanowires (NWs), nanobelts (NBs), nanoneedles (NNs), nanorods (NRs), nanotubes (NTs), and nanofibers (NFs), have gained widespread attention for various applications such as nano-electronics, nano-devices, dye-sensitized solar cells, biomedicine tissue engineering, Li-ion batteries, and nano-photonics. This study is focused on the synthesis procedure of various methods, characteristics, and properties of 1D nanostructures. Besides, ultra-modern 1D nanostructures-related studies have been covered and evaluated comprehensively to improve nanostructures' physical and mechanical properties and overall performance. Also, the 1D nanostructures can be the future in more applications such as energy source, medical, battery, etc., and dispense as an energy source with fossil fuels. This review paper contains the following sections: Synthesis methods, physical properties characterization, mechanical properties characterization of 1D nanostructures, the environmental effect, electrical and optical characterization, application of 1D nanostructures in energy storage, technical challenges, and limitations of the study, and conclusions. This review study gives the necessary fundamental knowledge regarding the 1D nanostructures as well as mechanical behavior towards their promising applications. The impact of these novel nanostructures towards a rapid advancement in future applications can be considered the next step to boost the knowledge to contribute substantially to the scientific community

Morphological and growth characteristics of template-assisted electrodeposited cobalt nanowires: Effect of synthesis current density and temperature

Processing conditions during the deposition process affect the nanowire properties significantly in template-assisted electrodeposition, an effective method for growing freestanding and well-dispersed nanowires. In this work, we study the effect of current density and temperature on electrodeposited cobalt (Co) nanowire synthesized via a template-assisted process. Scanning electron microscopy was used to study the morphology of formed cobalt nanowires with EDS analysis, confirming Co as the main element. In addition, the length and growth characteristics of the formed nanowires are analyzed and discussed

Thermal analysis of SUS 304 stainless steel using ethylene glycol/nanocellulose-based nanofluid coolant

Green cooling system usage in machining is getting favors to minimize the environmental effect such as pollutions. Around 20% of the machining cost is about coolant usage in flooded cooling technique. Even though coolant has a reasonably low cost, their handling and disposing cost are very high and also, threatening toxic contents, disposal of used coolant is a big problem as it can lead to hazardous effect to the machining operates as well as to the environment. As an alternative, a cooling technique known as minimum quantity lubrication (MQL) was introduced in the machining operation. For MQL technique, the coolant should exhibit superior properties which are effective in machining operation when compared with the conventional machining coolant which is metal working fluid (MWF). Owing to the technology advancements by nanotechnology in nanomaterial, the nanofluid is a promising coolant that can replace the conventional machining coolant. In the present work, ethylene glycol/nanocellulose-based nanofluid is evaluated in terms of its thermo-physical properties and its effectiveness in machining performances which is temperature distribution in cutting tool and compare its effectiveness with MWF. Its effectiveness is tested in turning machining operation of SUS 304 stainless steel using cemented tungsten-cobalt (WC-Co)-coated carbide cutting insert. The turning operation by using ethylene glycol/nanocellulose-based nanofluid coolant with 0.5 vol% which exhibit a superior thermal conductivity of 0.449 W/m K than 0.267 W/m K thermal conductivity of MWF at 30 °C. The recorded lower amount of heat transfer to the cutting tool is 863 J compared with 1130 J when using MWF. On the other hand, the maximum temperature reading recorded at chip formed by using MWF is 225 °C whereas by using nanofluid is 154 °C which promises lower temperature distribution to chip formed during the machining operation. Also, the functionality of nanofluid as a thermal transport during machining is proven via chip formation observation analysis and scanning electron microscope (SEM) with energy-dispersive X-ray (EDX) spectrum analysis

Solar energy: direct and indirect methods to harvest usable energy

The global energy demand is increasing substantially due to increasing population, industries, and technological development. The renewable energy sources can play vital role to cope up with the rising demand for energy and reduce greenhouse gas emissions. Solar radiation is a source of renewable energy from sun, and it can generate electrical and heat energies using appropriate harvesting techniques [1]. The solar energy can be employed in two forms, which are solar thermal and photovoltaics. The solar energy can be directly converted into electricity (by solar photovoltaics) or indirectly converted into heat energy (by solar thermal collectors). Although photovoltaic (PV) requires high capital cost, this technology is accepted worldwide due to less maintenance and operating cost

Morphological analysis of Polyaniline (PANI) integrated cotton fabric

With the exponential growth of flexible electronics, conductive polymer Polyaniline has been acting as a protagonist since its discovery. Polyaniline is endowed with optical and electrical conductivity, a low-cost synthesis process, and environmental stability. However, the irregular, rigid form and specific choice of solvents often hinder its widespread application. The conductive fabric can be used in the field of flexible energy harvesting, sensing, electromagnetic shielding or many more functional applications. In this study, conductive cotton fabric was fabricated using a facile in-situ chemical oxidative polymerization of Aniline on a Cotton fabric surface. Doping was performed using HCl, maintaining three different concentrations levels (1M, 2M and 3M). The color of Polyaniline turned from Blue (Emeraldine Base) to Emerald Green (Emeraldine Salt) upon its successful formation. Visual analysis, Scanning Electron Microscopy, Fourier-Transform Infrared Spectroscopy, and Energy Dispersive X-Ray Analysis were performed to justify the homogeneity and bonding adhesion with the fabric surface. It is observed that, the deposition of Polyaniline is much uniform and homogenous with the increase of dopant concentration

Parameter influence on the tensile properties of FDM printed PLA/ coconut wood

Due to its adaptability in allowing for individualized production, 3D printing technology has quickly become a viable option in the fabrication of parts. Recent years have seen a plethora of research devoted to enhancing the quality of 3D-printed components. However, the performance of the printed part depends heavily on the correct selection of process parameters for Fused deposition modelling (FDM), making it a significant task. Therefore, studying how different process parameters affect the final product's quality characteristics is essential. So, it's helpful if there's a good option for customizing the mechanical properties of 3D-printed components. This study aims to determine how factors affect the tensile properties of a composite made from PLA and coconut wood. The material in the form of a filament, such as thermoplastic polymers, was used. Coconut wood has been prized for centuries for its durability, beauty, and ecological friendliness. This research aims to create and compare the tensile properties of specimens featuring different infill patterns (concentric, cubic, gyroid, and triangle) and infill percentages (25%, 50%, 75%). Ultimate tensile strength of 37.21 MPa and elastic modulus of 1.12 GPa were achieved with the concentric infill pattern at 75% infill

Statistical model for impact and energy absorption of 3D printed coconut Wood-PLA

Fused deposition modeling (FDM)-3D printing has been the favored technology to build functional components in various industries. The present study investigates infill percentage and infill pattern effects on the printed parts’ impact properties through the 3D printing technique using coconut wood-filled PLA composites. Mathematical models are also proposed in the present study with the aim for future property prediction. According to the ASTM standard, fifteen specimens with different parameter combinations were printed using a low-cost FDM 3D printer to evaluate their impact properties. Statistical analysis was performed using MINITAB to validate the experimental data and model development. The experimental outcomes reveal the honeycomb pattern with 75% infill density achieves the highest energy absorption (0.837 J) and impact energy (5.1894 kJ/m2). The p-value from statistical analysis clearly shows that all the impact properties are less than the alpha value of 0.05, suggesting all the properties are vital to determine the impact properties. The validation process affirms that the generated mathematical model for the energy absorbed and the impact energy is reliable at an acceptable level to predict their respective properties. The errors between the experimental value and the predicted value are 3.98% for the energy absorbed and 4.06% for impact energy. The findings are expected to provide insights on the impact behavior of the coconut wood-filled PLA composites prepared by FDM-3D printing and a mathematical model to predict the impact properties

Preliminary Tensile Investigation of FDM Printed PLA/Coconut Wood Composite

Fused Deposition Modeling (FDM) is an of additive manufacturing method that has been used to create multiple components from a variety of materials for a wide range of applications in layer-by-layer deposition. The thermoplastic polymers were used as a material which comes in the form of a filament. Coconut wood is highly recognized for its naturally affable, ecological components, thermal resilience, and corrosion resistance up to the present day. However, PLA's characteristics embedded in coconut wood remain limited. The aim of this study is to create and analyse the tensile properties of the specimens with varying infill percentages (25%, 50%, and 75%) and the infill patterns (grid, rectilinear, concentric, honeycomb, and triangle) on coconut wood reinforced PLA using the FDM technique. The specimen is printed in accordance with the ASTM standard for tensile testing which is ASTM D638 type 1. Following that, the tensile properties of the PLA and PLA-coconut wood were analysed. The results demonstrate that the concentric infill pattern with a percentage of infill 75% of pure PLA produced 37.55 MPa of Ultimate tensile strength and the maximum elastic modulus of 1.148 GPa and yield strength of 23.33 Mpa in tensile testing meanwhile the Grid pattern has the weakest properties among all the patterns

Design and development of a biomimetic solar tree for sustainable cogeneration : An energy and exergy assessment

Solar energy is becoming an increasingly popular and important source of renewable energy. Solar trees have emerged as a novel and innovative approach to harvesting solar energy. Solar trees are artificial structures that mimic the shape and function of trees, with branches or leaves that contain photovoltaic cells to convert sunlight into electricity. The solar tree generates both electrical and thermal energy from solar radiation. The present study tested the thermal (module temperature, heat loss coefficient), electrical (power output), and operating parameters of a solar tree at Universiti Malaysia Pahang, Pekan, Malaysia, on a typical sunny day. First-law analysis and second-law analysis were carried out to determine exergy losses during the photovoltaic conversion process of solar trees. The data obtained from the experiment is utilized to determine the energy and exergy efficiencies of the solar tree. The energy efficiency ranges from 16.8% to 8.3% throughout the day, displaying some variability. However, as for the exergy efficiency of the photovoltaic solar tree under consideration, it is observed to be lower, ranging from 16.1% to 6.6% for electricity generation. It is observed that the exergy losses increased with increasing module temperature and a drop in exergy efficiency