Conventional electrochemical uric acid (UA) biosensors are often limited by rigid substrates, multi-step synthesis, and complex fabrication protocols. This study presents an ultrasensitive, energy-efficient, cost-effective, miniaturized, and label-free flexible UA biosensor based on a scalable Graphene/MoS2 2D heterostructure. 2D films of Graphene and monolayer MoS2 were grown via chemical vapour deposition (CVD) and integrated onto a flexible polyimide substrate with prefabricated interdigitated electrodes (IDE) using a single-step shadow masking technique to overcome the limitations of rigid substrates and complex fabrication protocols. Structural and optical characterization confirmed the crystallinity, uniformity, and defect-free monolayer quality of the 2D films. The electrochemical response of the biosensor evaluated through Cyclic Voltammetry (CV) and Differential Pulse Voltammetry (DPV) exhibits well-resolved redox peaks and intrinsic selectivity for UA over common interferents such as ascorbic acid (AA), folic acid (FA), urea, and thiourea without requiring surface functionalization. The device achieved an ultralow limit of detection (LOD) of 0.0214 pM (0.0036 pg/mL) and a high sensitivity across a wide dynamic range (1 pg/mL to 100 μg/mL), outperforming previously reported UA sensors. The enhanced performance arises from the Type-II band alignment due to the synergistic coupling of Graphene and MoS2. Graphene’s high electrical conductivity with MoS2’s strong surface affinity provides catalytically active defect-rich sites for specific UA adsorption. The integration of lightweight, biocompatible, mechanically resilient 2D nanomaterials into flexible platforms offers a promising pathway for high-performance, real-time health monitoring and personalized point-of-care diagnostics.

The increasing demand for advanced lightweight engineering materials has accelerated the development of hybrid aluminum matrix composites with enhanced mechanical and tribological performance. However, the relatively low hardness and poor wear resistance of conventional Al-Mg-Si alloys limit their application under severe service conditions, thereby necessitating the incorporation of suitable reinforcements to improve their overall performance. The present work investigates the synergistic influence of in-situ formed titanium diboride (TiB2) particle and graphite (Gr) reinforcements on the microstructural evolution, mechanical, and tribological properties of AA6063 alloy-based HMMCs. Hybrid metal matrix composites containing 2 to 6 wt. K_2 TiF_6 and KBF_4 salts for the in-situ synthesis of TiB2. The developed composites were characterized using optical microscopy, FESEM, and X-ray diffraction to examine the phase formation and microstructure. The mechanical properties of developed MMCs are measured through tensile strength, Brinell hardness, and impact properties; however, the tribological properties are measured through using a pin-on-disk wear testing setup under dry sliding conditions. Taguchi-based analysis was employed to optimize the wear parameters. The experimental results are analyzed using the signal-to-noise (S/N) ratio and analysis of variance (ANOVA) to determine the optimal process parameters and their significance. The results showed that there is an improvement in mechanical properties greatly with TiB2 content increasing due to an effective load transfer and grain refinement. The composite with 4 wt.

Biomedical procedures needed to be upgraded with time through various innovative techniques in order to enhance its efficacy. Graphene’s transformative potential in biomedicine owing to its unique physicochemical properties provides innovative platform in this regard. The current review begins with highlights on key attributes of graphene such as biocompatibility, surface functionalization potential, mechanical strength, and electrical/thermal conductivity. Further emphasis has been given to the graphene’s diverse roles, including nanocarriers for drug delivery, stimuli-responsive and targeted therapeutic strategies, biosensors for biomarker detection and their integration into wearable devices, and significant contributions to tissue engineering as well as regenerative medicine through scaffolds. Besides, its applications in bioimaging (MRI, fluorescence) and photothermal/photodynamic therapies are also discussed. Later part of review involves in vitro/in vivo biocompatibility and dose-dependent toxicity of graphene. Conclusively, the major challenges obstructing graphene-derivatives in biomedical applications are highlighted along with possible measures. Integration with emerging trends like AI and ML- empowered devices can underscore graphene’s promising role in next-generation biomedical platforms.

Zinc oxide nanoparticles (ZnO NPs) are among the most frequently utilized nanomaterials because they inhibit microbial growth; however, their precise mode of action (MOA) remains incompletely understood. This study details the synthesis of zinc oxide (ZnO) nanoparticles via the sol-gel method, selected for its high purity, homogeneity, and precise controllability. The research evaluates the impact of calcination temperature on the structural, morphological, and antimicrobial properties of the resulting particles. Characterization was conducted using X-ray diffraction (XRD), thermogravimetric analysis (TGA), and Fourier-transform infrared spectroscopy (FTIR) to determine crystallite size and surface composition. Additionally, the antifungal efficacy of the synthesized ZnO nanoparticles was rigorously tested against Saccharomyces cerevisiae to assess their potential as bioactive agents. The nanoparticles' ability to fight fungus was then assessed using the yeast strain Saccharomyces cerevisiae. The findings indicated that the ZnO nanoparticles did not demonstrate any antifungal effect against Saccharomyces cerevisiae. The minimal toxicity observed in both nano and bulk forms of ZnO towards this yeast is likely attributable to S. cerevisiae's notable tolerance for high concentrations of zinc ions.

Abstract High entropy alloys (HEAs) are an advanced class of multi-principal element materials, while semi-solid processing (SSP) is a well-established technique for conventional alloys but relatively unexplored in the context of HEAs. Although both HEAs and SSP have been extensively studied independently, only limited research has addressed SSP of HEAs. This paper reviews HEAs, their strengthening mechanisms, alloy design strategies, and manufacturing routes, followed by a discussion of SSP approaches applied to HEAs. Several HEAs demonstrate promising mechanical and radiation-resistant properties, suggesting potential applications in aerospace and nuclear sectors. SSP may promote globular microstructures and microstructural refinement, which can enhance mechanical performance depending on alloy composition and processing parameters. Cooling slope casting, a variant of SSP that has received limited attention for HEAs, represents a promising direction for future research.

Polylactic acid (PLA) is a biodegradable polymer widely employed in fused deposition modeling (FDM) 3D printing due to its sustainability and ease of processing from renewable resources. Despite its advantages, PLA exhibits inherent brittleness and anisotropic mechanical behavior, limiting its use in load-bearing applications. This study aims to address how the key 3D printing parameters—layer height, infill density, infill pattern, and raster orientation—can be optimized to enhance the mechanical performance of FDM-printed PLA components. Using the robust Taguchi design of experiments methodology, PLA specimens were systematically fabricated varying these parameters across multiple levels. Mechanical properties, including tensile strength, compressive strength, and hardness, were quantitatively assessed using standardized testing protocols complemented by microstructural analysis. Results demonstrate that a combination of a 0.1 mm layer height, 100

Fusion-based composite manufacturing faces challenges such as hot cracking, distortion, metallurgical incompatibility, and brittle intermetallic formation due to liquid–solid phase transformations. In contrast, friction stir additive manufacturing (FSAM) is an emerging solid-state additive manufacturing process that eliminates these issues by avoiding melting. A specially designed cylindrical tool generates frictional heat due to thermo-mechanical stirring action. The severe plastic deformation due to thermo-mechanical stirring often leads to an equiaxed, homogeneous, and refined microstructure, which in turn results in improved mechanical properties. This review paper discusses different types of FSAM processes and correlations that exist between the process parameters, microstructural characteristics, and mechanical performance. Factors like rotational speed (ω), translational speed (V), feed rate (F), and tool geometry do exert an influence on microstructural evolution. The recently developed friction stir powder additive manufacturing is elaborately discussed as it is gaining traction among researchers and industries. The friction-based additive manufacturing has the potential to become a viable alternative to fusion-based additive manufacturing technology. This paper also discusses the applications, challenges, and future scope of friction-based additive manufacturing processes.

Polyhydroxybutyrate (PHB) has gained attention as an excellent packaging material due to its high crystallinity, biodegradability, low interaction with food matrices, and favorable mechanical properties. This study explores the development of PHB films incorporated with potassium sorbate (KS) and gallic acid (GA) via solvent casting, followed by a 30-day biodegradation test in soil. The films are analyzed for physicochemical and microbiological properties using X-ray diffraction, tensile testing, and disk diffusion assays. The soil-buried PHB films demonstrate accelerated biodegradation, likely driven by increased microbial and fungal activity, as well as moisture absorption. Incorporating KS and GA significantly enhances the antimicrobial efficacy of the films against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, with greater inhibition observed against S. aureus. This difference may stem from the additional lipopolysaccharide membrane in E. coli. Field emission scanning electron microscopy (FESEM) of the films, both pre- and post-biodegradation, provides further insights into their structural changes. These findings underscore the potential of PHB antimicrobial films in advancing sustainable food packaging applications.

Barium zirconium titanate (BZT) has garnered considerable interest due to its tunable dielectric and ferroelectric properties, making it suitable for memory devices and multilayer capacitors. This study investigates the impact of lanthanum (La) doping (2

Yttrium (1 mol %) -doped 0.49BiFeO(3)-0.20Pb(Mg1/3Nb2/3)O-3-0.31PbTiO(3) ceramic at the morphotropic phase boundary was synthesized by a solid-state reaction via columbite precursor technique. X-ray diffraction (XRD) and FESEM analysis confirmed a perovskite phase in the P1m1 space group with a homogeneous microstructure sintered at 920 degrees C. Rietveld refinement yield lattice parameters a = 3.95984 angstrom, b = 3.93828 angstrom, c = 4.04466 angstrom, alpha = 90.000 degrees, beta = 89.970 degrees, gamma = 90.000 degrees. Studies of dielectric permittivity and ferroelectric hysteresis at room temperature shows Y doping impact, exhibiting low dielectric loss and a saturated hysteresis loop. The synthesized sample remains fatigue-free over 10(4) cycles, with a high value of converse piezoelectric coefficient of d(33)* similar to 723 pm/V. Weak ferromagnetism is observed in the magnetic hysteresis loop (M-H) at room temperature, suggesting potential applications in ferroelectric-based technologies.

Aluminum metal–matrix composites (AMMCs) were prepared by dispersing TiO2 dispersoids of different volume fractions into an AA6063 matrix via stir casting and subjected to process–structure correlation studies. Four different samples based on weight ratio were considered herein: 99Al-1TiO2, 97Al-3TiO2, 95Al-5TiO2, and the as-received AA6063. Their mechanical properties namely, microhardness, tensile strength, and tribological behavior, were determined. In addition, the microstructure of the samples was also analysed. It was observed that the addition of 5% TiO2 particles enabled the AA6063 matrix to accommodate a higher strain energy while providing the required driving force to generate dislocations and substructures. Therefore, considering the plastic deformation, the ultimate tensile strength σut increased gradually with the addition of TiO2 (in weight%). The flow curves of the 95Al-5TiO2 sample showed the highest value of σut, whereas the as-received AA6063 matrix exhibited the lowest value. For linear elastic deformation, AA6063 showed the lowest yield strength (σys) as compared to the AMMC samples for all TiO2 weight% values; however, the variation in σys among the AMMC samples was minimal. The microhardness of the samples increased gradually with the addition of TiO2, and the percentage reduction in area at the fracture was largest for 95Al-5TiO2. The Taguchi’s L9 array and variance analysis of the process parameters indicated that the material wear was largely affected by the normal load, followed by weight% of TiO2 and sliding speed. Wear surface characteristics, such as microvoids, delamination, microcracks, and wear debris, were qualitatively observed in all the AMMC samples. The overall strength improvement was attributable to the effects of addition of the dispersoids. During melt solidification, the TiO2 particles surpassed/pinned and hindered the grain growth, resulting in grain-size refinement.

Industries such as aerospace, robotics, defence, light aircraft, and transportation are increasingly in need of lightweight and strong materials. Aluminium-magnesium alloys are the preferred choice due to their high strength and stiffness-to-weight ratios compared to traditional materials. This study utilized an innovative technique called friction stir additive manufacturing (FSAM) to develop a laminated sheet of Al5083-AZ31B alloys for multipurpose applications. The effect of the rotational speed of the tool is examined over the microstructural features and bonding strength of the lamination. The study examined the macrostructural and grain refinement results at the interfacial layer through light microscopy, FESEM and EBSD analysis. XRD test has been conducted and discussed in terms of crystallographic planes and chemical compounds at the interfacial layer. To validate the specimen's bonding strength, tensile tests and Brinell hardness tests are conducted. The result reveals a higher ultimate strength of 297.25 MPa at 2000 rpm while lower strength is observed at 234.47 MPa for rotational speed at 1000 rpm. The maximum BHN of 71.1 is recorded at a rotational speed of 2000 rpm The strong interfacial compounds such as Al4Fe, and Mg2Al3 are supports the bonding strength and increase hardness.

Fused Filament Fabrication (FFF) is a promising 3D printing technology for industrial and technological applications due to its cost-effective ability to fabricate large, complex objects from thermoplastics. Nylon 12, a versatile thermoplastic, is widely used for functional prototyping and has significant potential for end-user applications. Our research focuses on enhancing the mechanical and thermal properties of Nylon 12 by developing composites with ceramic fillers such as zinc oxide (ZnO) and alumina (Al2O3). This is achieved by melt mixing the fillers into the Nylon 12 polymer matrix and preparing filaments using a filament extruder. The optimal concentration of these fillers was determined by analyzing tensile strength of the polymer composites, while DSC was employed for thermal analysis. Additionally, rheological studies were conducted to assess the impact of the fillers on the viscoelastic properties and flow characteristics of Nylon 12. The Carreau-Yasuda model was employed to study the complex viscosity of the materials. Our findings indicate that the addition of functional fillers enhances the shear thinning behavior of Nylon 12, improving material flow through the printer nozzle. This optimization leads to 3D printed structures with minimal dimensional inaccuracies, ensuring high-quality prints suitable for commercial applications.

Metal matrix composites (MMCs) have proved themselves a reliable alternative to different metals and their alloys due to their high strength-to-weight ratio, high durability; high wear corrosion resistance, high hardness and other mechanical properties. In the conventional approach, different methods like liquid-state processing (stir casting, squeeze casting etc.), solid-state processing (consolidation, physical vapour deposition or PVD, powder bending etc.), and in-situ processing are being used to manufacture metal matrix composites (MMCs). Injection molding and other in-situ processing are highly dependent upon particle size and morphology. Particle agglomeration is a common problem for liquid and solid-state processing. Again, these inhomogeneous second-phase particles influence crack initiation and propagation, thermal mismatches, residual stresses, and dislocation, making the subtracting or machining process challenging to perform. By observing these issues with the conventional approach, additive manufacturing can be considered an alternative technique to fabricating metal matrix composite. It is reported that 3D printing cannot only sort out the matrix/reinforcement bonding issues observed during conventional manufacturing processes but is also capable of providing a uniform distribution of reinforcement inside the metal matrix. Additive manufacturing allows the fabrication of functionally graded composites with any geometrical complexity, higher accuracy, and minimum production lead time. However, challenges like lack of fusion, rapid cooling, poor surface morphology and texture restrict the additive manufacturing processes to manufacturing a sound product. The current chapter summarises the recent development in manufacturing metal matrix composites (MMCs) using different additive manufacturing processes.

Additive manufacturing (AM) technologies offer various opportunities for manufacturing industries by fabricating parts from different materials, thereby increasing freedom of design and reducing lead time and production cost. A number of AM techniques are used to shape polymers, ceramics, metals, composites, biomaterials, and smart materials. Today shaping of biomaterials is high in demand, and various researchers are going on to fabricate biocomponents by different AM processes by keeping patient-specific needs in mind. The new capability for development in AM has appeared in the processing of smart materials and can change their dimensions and properties under the influence of certain external environments. Overall, this chapter provides an overview of various materials processed by AM techniques.

Ferroelectric delta-phase comprising polyvinylidene fluoride (delta-PVDF) thin films are prepared via spin-coating followed by high-temperature annealing and rapid ice quenching, where, the requirement of a high electric field (similar to MV/m) is circumvented. Herein, ferroelectric responses, that is, "write," "erase, " and "read" pulses on as prepared delta-PVDF thin film, have been demonstrated through piezoresponse force microscopy (PFM). A metal-ferroelectric-insulator-semiconductor (MFIS) diode containing delta-PVDF has shown a capacitance-voltage (C-V) hysteresis with a notable memory window of 7.5 V up to a temperature of 140 degrees C, overcoming lower fatigue temperatures, limited by Curie transition in co-polymer P(VDF-TrFE). A very stable polarization state is reflected by a holding period of a capacitance state of 10 h, where only a 5% loss of its initial value is noticed. The excellent ferroelectric response and retention behavior of the delta-PVDF thin film may open up new opportunities in the field of high-endurance non-volatile memories.

The main challenges for the manufacturing sectors are to provide product with lower costs, within shorter lead times, showing good esthetic improvement, being precise geometrically and dimensionally accurate, and having better mechanical properties for end use applications. Additive manufacturing (AM) is an emerging technology having the potential to provide solutions to the challenges of market globalization. Each AM system requires a series of preprocessing steps to convert the conceptualized idea of designer into the final part. The preprocessing steps are time- and source-consuming but are mandatory to obtain part fit in all respects. The degree of preprocessing differs from one AM system to another. The part printed by the AM technique is not ready to meet the customers’ requirements. It consists of geometric flaws like a too rough surface and poor mechanical properties. Various postprocessing operations are thus performed on the part to improve its characteristics and to make it suitable to the customers’ demand.

A recent innovation in energy resource consumption has propelled the implementation of a green energy source in the form of triboelectric nanogenerators (TENGs). The combination of 3D printing with TENG has generated larger ripples in the field of energy storage and distributed power supply technology. The current research focusses on developing fused deposition modeling (FDM)-based TENG devices using feedstock materials such as polylactic acid (PLA) and acrylonitrile butadiene styrene as tribopositive and tribonegative layers, respectively. This study emphasizes on the role of carbon nanotube-zinc oxide (ZnO) core-shell nanostructures reinforced into PLA by examining their impact on the final TENG output voltage. The presence of carbon nanotube-zinc oxide core shell (CNS) has enhanced the TENG output voltage (Voc) from 1 V to 8 V. Furthermore, FDM 3D printing parameters such as filling rate (%), layer thickness, and printing patterns have engaging influence on Voc. Our research identifies PLA/CNS layers comprising 20% filling rate as having a layer thickness of 0.1 mm, and a donut pattern obtaining the highest Voc (8.9 V). The reinforcement of CNS into PLA has also augmented its comprehensive properties including tensile strength and electrical conductivity. This research paves a path towards innovative fabrication strategies for TENG devices towards next generation portable electronic devices using FDM 3D printers.(c) 2023 Elsevier Ltd. All rights reserved.

Stainless steel (SS) coatings/claddings over aluminium alloy (AA) substrates have been practiced through friction surfacing, thermal and cold gas spraying, laser coating, and diffusion bonding. In this work, 304-grade SS is reverse-cladded to an LM25 AA through die-casting using a surface-prepared sheet insert. The clad-substrate interface was characterized micrographically and compositionally through optical and electronic microscopic techniques. Micrographs revealed that reverse cladding was achieved successfully by forming an intermetallic zone (IMZ). The IMZ contains four intermetallic layers (IMLs) of varying thickness with 6.42 & PLUSMN; 2.04 & mu;m near the central region. Electron probe microanalysis showed Fe3(Al, Si), Fe3(Si, Al), Fe(Al, Si), and Fe3Al15Si2 are the associated phases with four IMLs from the SS to AA side, respectively.

Pure and Mn-doped 0.49BiFeO 3 –0.20Pb(Mg 1/3 Nb 2/3 )O 3 –0.31PbTiO 3 (BF–PMN–PT) ceramics at morphotropic phase boundary (MPB) have been prepared by solid state reaction method. A systematic investigation of its microstructure and electrical properties was conducted. Powder X-ray diffraction (XRD) and Field emission scanning electron microscope (FESEM) showed the formation of pure perovskite phase with homogeneous microstructure having average grain size of 2.48 µm at optimum temperature 920 °C. As compared to the pure BF–PMN–PT ceramic, enhanced dielectric constant value (~ 800) was observed for Mn-doped sample at room temperature. Polarization vs. electric field (P–E) hysteresis curves exhibits improved ferroelectric properties (P r = 97.65 C/cm 2 at coercive field E c = − 17.08 kV/cm) after doping and showed a fatigue free nature over 10 4 switching cycles. The displacement voltage (D–V) curve showed a high value of the piezoelectric coefficient d 33 * = 786 pm/V after Mn doping. The magnetic hysteresis loop (M–H) curve showed a weak ferromagnetic nature with coercive field (H c = 54.19 Oe) and remanent magnetization (M r = 0.0087 emu/g) of the sample. Therefore, Mn-doped BF–PMN–PT ceramic can be a promising candidate for applications in the electronic ceramic industries.