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This article presents the mechanical, physical, and tribological properties of the boron carbide (B4C) reinforced epoxy matrix composites (BEMCs). The BEMC samples were prepared with various B4C concentration of 0%, 1%, 2%, 3%, and 5%. B4C particles were treated with a silane coupling agent to ensure efficient adhesion with epoxy. The influence of a range of parameters (particle loading, sliding speed, sliding distance, and normal load) on the wear and friction behavior of BEMCs were evaluated by conducting wear tests under dry sliding conditions on a pin-on-disc wear test set-up. The addition of B4C to the epoxy polymer improved the wear resistance of the composites. Maximum wear resistance and coefficient of friction were observed for the composite with the highest percentage of B4C (5%). The specific wear rate was reduced on increasing load and sliding distance and increased with the sliding velocity. Mechanical properties including compression strength, flexural strength, and impact energy, along with physical properties such as density and hardness, were also evaluated. B4C particles improved the hardness, density, flexural and compression strength, and impact resistance of the composites. Scanning electron microscope (SEM) analysis of the worn-out surfaces and flexural fractured surfaces was carried out to predict the possible wear and fracture mechanisms. Micro-ploughing, abrasion, and adhesion were the wear mechanisms in BEMCs. Under the flexural loads, particulate de-bonding, pull-out, and brittle fracture of the matrix were the governing failure mechanisms.

India is among the largest producers of sugarcane in the world. Sugarcane bagasse (SCB) has been used in different applications in the area of sugar and its products, biomedical sciences, biotechno...

Alumnium alloy LM 25 based composites reinforced with boron carbide at different weight fractions of 4%, 8%, and 12% were fabricated by stir casting technique. The microstructures and morphology of the fabricated composites were studied by scanning electron microscopy and energy dispersive spectroscopy. Elemental mapping of all fabricated composites were done to demonstrate the elements present in the matrix and fabricated composites. The results of microstructural analyses reveal homogenous dispersion of reinforcement particles in the matrix with some little amount of clustering found in composites reinforced with 12% wt. of boron carbide. The mechanical characterization is done for both alloy LM 25 and all fabricated composites based on hardness and tensile strength. The hardness increased from 13.6% to 21.31% and tensile strength 6.4% to 22.8% as reinforcement percentage of boron carbide particles increased from 0% to 12% wt. A fractured surface mapping was also done for all composites.

The objective of this study was to develop a natural fiber-based composite with fibers extracted through a simple technique called a steam explosion. These environment friendly materials having deterioration rate greater than that of the other polymer-based materials commonly used in manufacturing industries. During this study, the cellulose nanofibers were extracted from a hemp fiber with the help of steam explosion technique. To confirm its suitably for bio-based composites structure implementations, the characteristic features and morphological properties were meticulously studied. The chemical characterization of Hemp fiber material exhibited a rise in cellulose content from 64% to 95%, due to bleach, alkali and acid therapies. Scientific evidence confirms that non-cellulosic compounds extraction such as lignin and hemicellulose that occur in acid, steam explosion and bleaching treatment, as observed in chemical properties during pre and post chemical fiber therapy. Scanning electron microscopy studies indicates that a decrease in the fiber-diameter aspect ratio and the percentage yield of nano-fiber removed by such a procedure is found to be very high compared with other conventional approaches during steam explosion with acid treatment. X-ray diffraction analysis exhibited the crystallinity of fiber contained crystalline cellulose was increased due to performed procedure. The composite developed with the reinforcement of the steam explosion process demonstrate increased mechanical properties such as hardness, tensile strength and toughness of the material used (Epoxy LY 556 and Hardener HY 951). The cellulose fiber-reinforced composites were processed after obtaining the cellulose fiber from the steam explosion process. Mechanical properties such as harness, tensile strength and toughness were significantly improved.

Plant base cellulose nanofibers with diameter 20–50 nm are obtained by Agave gigantea through the steam explosion method. These nanofibers used as a reinforcement to making composites at different percentages (10%, 15%, and 20%) with epoxy LY556 & hardener HY951 used as a matrix at a 10:1 ratio. Thermoset polymer is used as a matrix although it has a great strength-to-weight ratio, and performance, and good thermal properties. Preparation of composite used hand-lay-up method with random orientation of fibers, examining the mechanical properties of nanofiber-reinforced polymer matrix composites like tensile testing, impact testing, and hardness of the composites. The percentage of nanofibers has greatly influenced the mechanical properties of the material. The significant enhancement of mechanical characteristics was observed as the result of addition of nanofibers as a reinforcement in composites. Finding the percentage of absorption of moisture for the different samples at the same period and the rate of water absorption depend on the percentage of fiber used in the composite. It is directly proportional to the percentage of fibers and is the only the demerit when using plant base nanofiber as reinforcement.

The purpose of this investigation is wear characterization of solid glass microspheres (SGM) and boron carbide (BC)-reinforced epoxy composites, under dry sliding conditions using a pin-on-disk wear test machine. Influence of parameters like sliding distance, sliding velocity, applied load and addition of fillers, on the wear rate were examined. Taguchi technique was used for the plan of experiments to conduct wear tests. To evaluate the effect of the individual parameters on the rate of wear performance of composites, analysis of variance (ANOVA) and an orthogonal array were employed. Linear regression analysis was employed for all the composites to establish an empirical relation between the various process parameters and wear. The results indicate reduction in wear of polymer on addition of particulates with the lowest wear rates observed in composites with addition of boron carbide as filler. Different fracture mechanisms were revealed by Scanning electron microscope (SEM) images of worn-out composite surfaces.

This article is a review of the properties of boron carbide (B4C)-reinforced polymer composites. B4C have recently become attractive to researchers, engineers, and scientists as an alternative rein...

Present work represents the preparation of metal-metal (Al-Cu) functionally graded materials (FGMs) using powder metallurgy followed by sintering. The Al-Cu FGMs are developed by fine Al powder (purity 99.9%, 200 mesh) and copper powder (purity 99.9%, 300 mesh). The proposed composition of the graded material includes multilayered composite layers of varied Cu compositions (90 wt%, 80 wt%, 70 wt%, 60 wt%, 50 wt%, 40 wt%, 30 wt%, 20 wt%, 10 wt%). Optical microscopy and SEM images, has been taken for each sample to discuss the morphological aspects to validate the developed material. Results revels the successful development of FGM in terms of micro structural observations.

This research work is carried out to study the mechanical and wear behaviour of inorganic particle filled polymers. The usage of polymers especially epoxy resin is of considerable significance in the engineering field for a substantial period of time. Epoxy matrix filled with varying ratios of Solid glass microspheres (SGM) were fabricated using mechanical stirring process. The weight percentage of SGM were varied from 0 – 30, with a step size of 5wt%. Effect of weight percentage of SGM particles on bending strength, compression strength and compression modulus of the composites was evaluated. The Wear resistance of the composites against En-32 steel disk, was evaluated in terms of mass loss for various ratios of SGM using pin-on-disk test rig. Besides these, density of the composites was also evaluated. Mechanical and wear properties of the composites were improved by adding suitable percentage of the filler. Moreover density increased with the increase in percentage of SGM particles in the composites. Thus, the mechanical and wear properties of the epoxy can be improved by including solid glass microspheres in suitable percentage.

C-type natriuretic peptide (CNP) is the major natriuretic peptide of the central nervous system and acts via its selective guanylyl cyclase-B (GC-B) receptor to regulate cGMP production in neurons, astrocytes and endothelial cells. CNP is implicated in the regulation of neurogenesis, axonal bifurcation, as well as learning and memory. Several neurological disorders result in toxic concentrations of ammonia (hyperammonaemia), which can adversely affect astrocyte function. However, the relationship between CNP and hyperammonaemia is poorly understood. Here, we examine the molecular and pharmacological control of CNP in rat C6 glioma cells and rat GPNT brain endothelial cells, under conditions of hyperammonaemia. Concentration-dependent inhibition of C6 glioma cell proliferation by hyperammonaemia was unaffected by CNP co-treatment. Furthermore, hyperammonaemia pre-treatment (for 1 h and 24 h) caused a significant inhibition in subsequent CNP-stimulated cGMP accumulation in both C6 and GPNT cells, whereas nitric-oxide-dependent cGMP accumulation was not affected. CNP-stimulated cGMP efflux from C6 glioma cells was significantly reduced under conditions of hyperammonaemia, potentially via a mechanism involving changed in phosphodiesterase expression. Hyperammonaemia-stimulated ROS production was unaffected by CNP but enhanced by a nitric oxide donor in C6 cells. Extracellular vesicle production from C6 cells was enhanced by hyperammonaemia, and these vesicles caused impaired CNP-stimulated cGMP signalling in GPNT cells. Collectively, these data demonstrate functional interaction between CNP signalling and hyperammonaemia in C6 glioma and GPNT cells, but the exact mechanisms remain to be established.

Preparing the hybrid composite material using LY556 epoxy resin and HY951 hardener was used as the matrix and agave nano fibers with zinc powder use as reinforcement, mixing with help of stirrer at 800 rpm. There are various methods of fabrication technologies are available but here are using hand lay-up method. Study the surface morphology of raw and chemical treated fibers also finding the material used for the hybrid composite is reinforced agave furcrea fibers and zinc powder at different percentages.

Ceramic materials, like Aluminium Oxide (Al2O3), have high mechanical strength, high wear resistance, high temperature resistance and good chemical durability. Powder metallurgy processing is an adaptable method commonly used to fabricate composites because it is a simple method of composite preparation and has high efficiency in dispersing fine ceramic particles. In this research copper and novel material aluminium oxide/copper (Al2O3/Cu) composite has been fabricated for the application of electrode in Electro-Discharge Machine (EDM) using powder metallurgy technique. Al2O3 particles with different weight percentages (0, 1%, 3% and 5%) were reinforced into copper matrix using powder metallurgy technique. The powders were blended and compacted at a load of 100MPa to produce green compacts and sintered at a temperature of 574 °C. The effect of aluminium oxide content on mass density, Rockwell hardness and wear behaviour were investigated. Wear behaviour of the composites was investigated on Die-Sink EDM (Electro-Discharge Machine). It was found that wear rate is highly depending on hardness, mass density and green protective carbonate layer formation at the surface of the composite.