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Automobile and aviation industries require lightweight solutions in the suspension system to improve overall performance and payload capacity. This can be achieved by materials having high strength to weight ratio. Fiber composites, known for their lightweight and high strength, face a major issue of delamination, which shortens the lifespan of fiber‐reinforced polymer leaf springs. Current researchers are emphasizing the use of functionally graded materials as a promising alternative to tackle this problem. In the present work, a functionally graded leaf spring plate was fabricated using stir casting technique with five layered gradations in the mid portion. The amount of molten material required for each gradation was ensured using a novel experimental technique. On the other hand, the matrix and reinforcement have been adopted from the output of the analysis conducted using CES EduPack 2019 software. Low density and high fatigue strength were primary focal point for the consideration of matrix and reinforcement materials. Aluminium 7075 and boron carbide were considered as matrix and reinforcement materials respectively. Stir casting technique, used in the present work, is simple, suitable and cost effective technique which creates a gradation at central part of the leaf. [ABSTRACT FROM AUTHOR]

In this study, authors reinforced micro (0–10 wt%)- and nano (0.8–1.8 wt%)-Al2O3 particles into the AA7075 matrix to enhance wear resistance. Comprehensive microstructural analysis, including optical microscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy, confirmed the development of robust intermetallic compounds and uniform distribution of reinforcements. Using XRD analysis, peak detection of the Al2O3 and MgZn2 was observed. Al, Al2CuMg, and Al8Fe2Si were identified as the primary phases, and monolithic and composite materials both showed minor MgAl2O4 formation. Ball-on-flat tests (5 and 10 N loads) assessed wear and friction behaviors. Potentiodynamic polarization tests were employed to examine the corrosion behavior of both the monolithic alloy and the manufactured composites. The composite with 1.8 wt% nano-Al2O3 at a 5 N load demonstrated a 53% lower wear rate and 16% reduced friction. Predominant wear mechanisms included abrasive, oxidative, adhesive, and delamination. Corrosion test findings indicated that the composite containing (0.8 wt% nano-alumina and 5 wt% micro-alumina) exhibited superior corrosion resistance compared to the monolithic alloy and other composites. [ABSTRACT FROM AUTHOR]

Introduction: In this study, we focus on enhancing the optical properties of PEDOT:PSS thin films by incorporating pure Sn nanoparticles (NPs) synthesized using the ultrasonic ablation technique. The objective is to investigate the impact of Sn concentration on the optical characteristics of the films, with a specific emphasis on applications in organic solar cells. Methods: We systematically varied the concentrations of Sn in PEDOT:PSS thin films and characterized their optical properties. The index of refraction (n) and extinction coefficient (k) were precisely determined by analyzing the transmission and reflection spectra of the films. Additionally, Sellmeier's dispersal model was employed to elucidate the obtained results of n, and dispersive factors were calculated and interpreted. Results: The incorporation of Sn nanoparticles led to improvements in the energy bandgap (Eg) values of PEDOT:PSS films. Notably, as the concentration of Sn increased, the n values decreased, indicating enhanced suitability for organic solar cell applications. The study also unveiled a decrease in the dielectric constant of PEDOT:PSS/Sn films with increasing Sn content, resulting in improved transmittance velocity and enhanced efficacy of microelectronic devices. This, in turn, promotes the development of large-frequency and large-velocity stretchy circuit boards. Discussion: The comprehensive assessment of optical and dielectric parameters, including complex dielectric constant, complex optical conductance, and nonlinear optical constants, provides valuable insights into the potential applications of PEDOT:PSS/Sn films. The larger nonlinear optical constants observed in the present films suggest their suitability for diverse applications such as all-optical switching, limiting, phase modulation, and frequency conversion. Overall, our findings highlight the promising potential of Sn- incorporated PEDOT:PSS thin films in advancing the field of optoelectronics and microelectronics. [ABSTRACT FROM AUTHOR]

The present study focuses on the investigation of mechanical, thermal, and corrosion behaviors of cast hybrid nano-metal matrix composites of AA7075 with Al2O3 and coconut shell ash (CSA) nano- and micro-sized particulates, respectively, as reinforcements. Using an ultrasonic assisted stir-casting technique, the hybrid composites were fabricated using 2, 4, and 6% by weight of CSA and 0.5% by weight of Al2O3 in equal proportions. SEM, EDS, XRD, porosity, tensile, damping, dislocation density, coefficient of thermal expansion, and polarization tests were used to characterize four different combinations. The findings indicated that the nano- and micro-sized particulates were spread evenly in the matrix. The dislocation density, which is caused by a thermal mismatch between the matrix and the reinforced particles, as well as composite porosity, have been found to have a significant impact on the damping behaviors of hybrid composites. Also, the thermal expansion coefficient of HMMCs decreased with the addition of Al2O3 and CSA. The corrosion resistance was gradually increased by increasing the weight percentage of reinforcement in the AA7075 matrix. [ABSTRACT FROM AUTHOR]

The present work is focused on the influences of reinforced particles on mechanical, microstructural, and tribological performances of AA7075 hybrid metal–matrix composites (HMMCs). Al2O3 and coconut shell ash (CSA) were reinforced using two-stage stir casting by varying the wt% (0–5) of reinforcement. Microstructural analysis and various phase identifications were examined with the help of scanning electron microscope (SEM) equipped with EDX and optical microscope. Various mechanical testing such as tensile, hardness, 3-point bend test, and tribological behaviors were carried out to know the HMMCs properties. Microstructural images revealed a homogeneous distribution of reinforced particles in the metal–matrix and EDX confirmed the presence of dispersed reinforcements (Al2O3 and CSA) in the HMMCs. It was seen that mechanical properties and tribological behavior have been increased after addition of Al2O3 and CSA reinforced particles whereas slightly decreased in impact strength. Transgranular cleavage facets, micro-void coalescence, dimples, and crack were shown in SEM images of fractured specimens during impact and tensile testing. [ABSTRACT FROM AUTHOR]

We report the room temperature synthesis of ZnS in the wurtzite phase by using ethylenediamine, which acts as a template as well as a capping agent. With the addition of ethylenediamine, structural transformation in ZnS from cubic to wurtzite phase is observed. This is accompanied by an increase in the real permittivity by an order of 2, and reduction in dielectric loss by a factor of 6 as compared to a sample without ethylenediamine. Thus, suggesting that ethylenediamine capped wurtzite ZnS is more suitable for miniaturied capactive devices. [ABSTRACT FROM AUTHOR]

In this article, we have studied the structural, magnetic, optical, and photocatalytic properties of Bi1−xCaxFe1−xNixO3 multiferroics synthesized by sol–gel method. X-ray diffraction predicted the superposition of two structural phases (rhombohedral-R3c + orthorhombic-Pnma) for (x = 0.05, 0.10) samples. Correspondingly, drastic variations in the Raman modes were detected at low and high wavenumbers with increasing the Ca–Ni content. The larger change in the magnetic parameters at room temperature was identified for Bi0.90Ca0.10Fe0.90Ni0.10O3 nanoparticles caused by the formation of a new orthorhombic phase. The XPS spectroscopy study supported the magnetic enhancement in x = 0.10 samples due to increasing concentration of Fe2+, Ni2+ ions, and oxygen vacancies. The shift of ESR pattern with doping agrees with the magnetization values. The energy band gap values were altered by increasing the Ca–Ni content in BiFeO3 samples, from 2.22 to 2.05 eV. The photocatalytic activity of Ca–Ni doped BiFeO3 photocatalyst showed higher degradation rate (− 0.035/min) of Methylene blue (MB) in comparison to pure BiFeO3. [ABSTRACT FROM AUTHOR]