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The mechanical properties of components manufactured by fused filament fabrication lack sufficient levels for industrial applications. The need for post-processing is, therefore, necessary to enhance the interlayer strength and mechanical characteristics. In the present study, experimental analysis of the effects of annealing on polycarbonate acrylonitrile butadiene styrene manufactured by fused filament fabrication is explored. Annealing temperatures are selected in the range from 90 to 210[degrees]C based on differential scanning calorimetry analysis. The ultimate tensile strength improved by 20.39% from 32.39 to 38.99 MPa after the heat treatment at 180[degrees]C for 1-h duration. Flexural strength showed a remarkable enhancement of 53.21% after annealing at 180[degrees]C for 2 h. The interlayer diffusion and bonding are boosted following heat treatment and microstructural imaging proved the same although the surface had flakes due to the high heat exposure. X-ray diffraction testing of annealed models demonstrated a maximum crystallinity index of 32.56% when compared with nonannealed samples with 6.58%. The addition of polycarbonate to acrylonitrile butadiene styrene improves the stiffness and impact loading capacity with high heat resistance. The heat treatment process is capable of magnifying the mechanical characteristics of the end functional components, thereby opening up the scope for more engineering applications. KEYWORDS crystallinity, flexural strength, fused filament fabrication, heat treatment, tensile strength, orcid.org/00000001-9725-6640 1 | INTRODUCTION Fused filament fabrication (FFF) is an extrusion-based layer-by-layer 3D printing methodology producing consumer-specific components. The possibility to integrate any complex customizations to the target 3D item [...]

The shift from rapid prototyping to rapid manufacturing using 3D printing is prominent after the development of volumetric 3D printing, multi-material printing, and functional materials development. Fused filament fabrication (FFF) is a fast-growing additive manufacturing technology with widespread end-user applications. The key constraints to its growth are the lower surface and mechanical properties compared to conventional manufacturing paradigms. The goal of this review is to look at the numerous pre-processing and post-processing parameters for the property enhancement of FFF. Preprocessing methods included optimization of process parameters (infill percentage, pattern, layer height, nozzle and platform temperature, raster angle and width, build orientation, and air gap) and adaptive slicing techniques. Mechanical (hot air jetting, barrel finishing, sand blasting, laser polishing, etc.), chemical (vapor smoothing, dipping, plating, and painting), and thermal (thermal annealing and normalizing) post-processing techniques were successful in improving the mechanical strength and surface finish of fused filament fabricated parts. This paper outlines the various methodologies a FFF user could incorporate for enhancing the final finished product's properties. The potential future prospects for the development of the 3D printing sector are also examined. KEYWORDS adaptive slicing, additive manufacturing, fused filament fabrication, mechanical strength, post-processing, process parameters, surface finish, 1 | INTRODUCTION The technology advancements and new functional materials had helped in the transition of layer-by-layer additive manufacturing from mere rapid prototyping to rapid manufacturing and further. [1] The [...]

The purpose of the present investigation is to examine the heat, mass and microorganism concentration transfer rates in the magnetohydrodynamics (MHD) stratified boundary layer flow of tangent hyperbolic nanofluid past a linearly, uniform stretching surface comprising gyrotactic microorganisms as well as nanoparticles. The governing PDEs with relevant end point conditions are molded into a non-dimensional ordinary differential equation (ODE) form by means of the similarity transformation. The numerical solution of dimensionless problem is acquired within the frame of robust Keller-Box technique. The velocity, temperature, mass and motile microorganism density are investigated graphically within the context of different significant parameters. Numerical results have been inspected via plots and table (namely as the local Nusselt number, the local wall mass flux and the local microorganisms wall flux). This article proves that the energy, concentration and motile microorganism density reduce with increase in thermal, solutal and motile density stratification parameters. The asserted outcomes are beneficial to enhance the cooling and heating processes, energy generation, thermal machines, solar energy systems, industrial processes etc.

Electrical discharge machining (EDM) is a nontraditional machining process known for processing of hard, brittle and difficult-to-machine materials. EDM is precisely known for machining of conductive materials, but recent advancements in material processing techniques and machining technology have shown that there is a great possibility in the machining of non-conductive materials using EDM. Existing researches proposed important processing methods for EDM of non-conductive materials. However, there is a need for a collective study showing the ease, merits and limitations of suggested methods. In a similar direction, this article is aimed at presenting a critical insight on machining of non-conductive materials using EDM. This article is devoted toward exploring the several possibilities of machining non-conductive materials by EDM. Research survey was carried out by collecting research papers using "EDM" and "Non-conductive" materials as the keywords. Research papers were collected from Scopus and web of science from 2008 to 2023. The presented study is expected to help the researchers and practitioners to choose the machining method wisely and effectively to satisfy the EDM of non-conductive materials. [ABSTRACT FROM AUTHOR]

The present study investigates the mode‐II fracture resistance and interlaminar shear strength (ILSS) in glass epoxy laminates with the aid of glass‐carbon veils hybrid interleaving technique. Hybrid interleaves were prepared using various areal densities of non‐woven carbon and glass veils. Two methods, specifically inter‐ply and inter‐weaved ply interleaved glass epoxy composite laminates were manufactured by hand layup technique. End notch flexural and short beam test specimens were tested to estimate the mode‐II fracture resistance and ILSS. Test results indicated that the interleaved with inter‐weaved veil composite exhibited ~58% to ~82% and ~13% to ~61% enhancement for inter‐ply veil composite laminates when compared to plain samples. In context with the short beam test, a significant enhancement of approximately 23% in ILSS was noticed for the plain inter‐weaved veil constructed with a lower areal density of the carbon veil. Finally, the plain inter‐weaved interleaving technique has a prominent role in enhancing the resistance to fracture and shear strength in Glass epoxy laminates. Further, the fracture mechanisms of non‐interleaved and hybrid ply interleaved composite laminates were observed by scanning electron microscopic images. Highlights: Interleaving non‐woven microfiber veil is the most promising and cost‐effective strategy to enhance the Interlayer toughness and strength.Interleaving techniques used in this investigation have a significant effect on interlaminar fracture toughness (IFT) and interlaminar shear strength (ILSS).The areal density of high‐modulus carbon veil showed a different phenomenal influence on IFT and ILSS. [ABSTRACT FROM AUTHOR]

The requirement for post-processing methods in 3D printing has increased due to its major limitations such as poor mechanical and surface properties. Thermal annealing, a heat-treatment procedure, has proven to be an excellent approach for increasing the mechanical strength of additive manufactured thermoplastics. The optimized thermal annealing parameters for maximum tensile strength are identified. The Adaptive Neuro-fuzzy Inference System (ANFIS) methodology is employed in this study to forecast the tensile strength of thermal annealed fused filament fabricated polylactic acid (PLA), carbon fiber filled polylactic acid (PLA-CF), and polycarbonate acrylonitrile butadiene styrene (PC-ABS). The root mean square error (RMSE) of the predicted tensile strength of PLA, PLA-CF, and PC-ABS are obtained as 1.012, 0.5, and 0.835 respectively. The coefficient of determination for the predicted model of thermoplastics PLA, PLA-CF, and PC-ABS is determined as 0.98, 0.99, and 0.89 respectively. The ANFIS model developed is successful in determining the tensile strength of annealed 3D printed thermoplastics at various annealing conditions of temperature and duration. Further, the study investigates the effect of heat treatment on the compressive, impact, and flexural properties of PLA prints. [ABSTRACT FROM AUTHOR]

The mechanical properties of fused filament-fabricated specimens are the primary considerations of researchers. Process parameters have a significant impact on the mechanical strength of 3D-printed parts. In this work, the effect of process variables such as infill volume, pattern, layer height, nozzle temperature, and print speed on tensile and compressive strength of polylactic acid samples are investigated. The maximum tensile strength of 27.87 MPa was obtained at 90% infill density for gyroid pattern of a layer thickness of 0.1 mm at a nozzle temperature of 220°C and print speed of 30 mm/s. The maximum compressive strength of 38.21 MPa was achieved at 90% infill density for the triangle pattern of a layer thickness of 0.1 mm at a nozzle temperature of 220°C and print speed of 30 mm/s. Thermal annealing as a post processing method to enhance the mechanical properties is also explored. The effect of annealing temperatures 65°C, 95°C and 125°C and time 30, 60 and 120 minutes on mechanical strength were studied. Ultimate tensile strength showed an improvement of 25.26% to achieve 34.91 MPa whereas compressive strength increased by 21.87% to give 46.57 MPa strength. [ABSTRACT FROM AUTHOR]

In this paper, the effect of integration of natural fibers in UD carbon fiber is studied. The integration of natural fibers in carbon fiber is made via intra fiber hybridization. Natural fiber hybrid composite samples were prepared for Mode I and Mode II fracture tests. XRD analysis was done for the chosen natural fibers to know the crystallinity index and then compared with Carbon and Glass fibers. The fracture test experimental results, revealed that the effect of Jute fiber integration in UD Carbon epoxy composite was found significant in getting relatively good Mode I and II fracture toughness at the crack initiation without losing its stiffness. In addition to this Kenaf Carbon epoxy composite indicated better crack suppression with 30% higher propagation toughness values as compared to other hybrid combinations and pristine composites. It is observed that integration of jute fibers in UD carbon epoxy composites was significant in achieving good mode I and mode II fracture toughness at the crack initiation without losing its stiffness and also kenaf carbon epoxy composites indicated better crack suppression with 30% higher propagation toughness as compared to other hybrid combinations used. [ABSTRACT FROM AUTHOR]

Summary: This study presents the numerical investigation of the performance improvement of Metal Hydride (MH) bed equipped with nano‐enhanced phase change material (NePCM) jacket for heat reaction recovery via U‐tube heat exchanger using Nanofluid. In this study, Mg2NiH6 is used as an MH bed, sodium nitrate (NaNO₃) as heat storage medium (PCM), and sodium‐potassium nitrate (60% NaNO₃‐40% KNO₃) as a heat transfer fluid (HTF). A computational model for this system is developed and validated. Furthermore, the hydriding of the MH bed, the melting of NePCM, and the overall heat transfer characteristics are simulated. With this model, the effect of a few types of nanoparticle additives on the hydriding process is investigated. The nanoparticles of iron oxide (Fe2O3) and copper oxide (CuO) are dispersed at various concentrations (to a range of 0‐1.5 wt.%) in the HTF. Further, CuO and graphene nanoparticles are added to the PCM to a range of 0 to 5 wt.%. The simulation shows that a reduction of hydriding process time by 33.5% is possible by using this MH‐Nanofluid‐NePCM system in comparison with a conventional MH bed system. The use of nanoparticles in the HTF, at an optimum flow rate, did not show a significant effect on the enhancement of the hydriding process. Also, the results show that CuO‐PCM composite has a greater impact in decreasing the time of complete hydriding relative to graphene‐PCM composite. [ABSTRACT FROM AUTHOR]

Latent heat thermal energy storage (LHTES) systems and their applications have been very substantive for the developments in energy science and engineering. The efficiency of LHTES systems largely depends on the thermal conductivity of the phase change materials (PCMs) and the heat transfer mechanisms in them. This review focuses on the methods employed to enhance heat transfer in LHTES systems which accordingly improve their storage performance. This includes the possible geometrical configurations of LHTES systems and the effects of their design parameters. The various methods adopted for enhancing LHTES systems' performance through either applying nanomaterials additives, using cascaded or encapsulated PCMs, or employing extended surfaces, such as fins, are discussed in detail. Additionally, various designs of PCM based heat exchangers with active and passive heat transfer techniques were highlighted. These systems are critically analyzed to help selecting reliable techniques and compatible materials for effective designs in order to achieve more efficient LHTES systems. This review would be helpful for the researchers to further develop heat transfer intensification mechanisms in LHTES systems. [ABSTRACT FROM AUTHOR]

Highlights Present study comprehensively explores the phenomenon of in‐plane fiber waviness in glass/epoxy fiber reinforced polymer (GFRP) composites. Utilizing a pioneering technique that employs a semi‐circular bar to induce controlled fiber waviness, coupled with image processing using OpenCV library in Python coding for precise measurement and analysis of in‐plane fiber waviness. This defect is commonly found in components fabricated with fiber‐reinforced composites. During the process of manufacturing fibers may deviate from their intended orientation due to process variables or resin flow dynamics. Understanding in‐plane fiber waviness is crucial due to its impact on mechanical properties of composites. It is essential for optimizing manufacturing processes and ensuring enhanced structural performance in diverse engineering applications through analysis of strength and failure mechanism. A novel study was conducted by introducing a circular cutout within the fiber waviness region to investigate the combined effect of multiple defects. The experimental tensile test reveals that as waviness ratio (WR) increases a significant decrease in its tensile strength and vice versa. The study incorporates scanning electron microscopy (SEM) image analysis to examine composite failure. By advancing the understanding of in‐plane fiber waviness and its implications, this research significantly contributes to ongoing efforts in composite design and optimization. Adopting a cutting‐edge method to create controlled fiber waviness that makes use of a semi‐circular bar. Image processing with Python code that makes use of the OpenCV package to precisely measure and analyze in‐plane fiber waviness. A new investigation was carried out to examine the combined effect of multiple flaws by creating a circular cutout within the fiber waviness zone. [ABSTRACT FROM AUTHOR]