Fractography and Tensile studies on the effect of different carbon fillers reinforced hybrid nanocomposites

The use of elastomers has become increasingly important in a variety of industries, including automotive, medical, and food packaging. The adaptability of elastomers to different mechanical stresses has made them a popular choice for these applications. However, the mechanical properties of elastomers can be further enhanced by adding suitable fillers. In this study, the effects of different carbon fillers, namely carbon black, carbon graphite, and carbon nanotubes, on the tensile strength of elastomeric materials were investigated. Different combinations of plain silicone with varying concentrations of CB, CG, and CNT fillers were prepared using a solution casting method. The concentrations of the fillers ranged from 5% to 15% with an interval of 5%. The tensile strength of each combination was measured, and the results showed that the maximum tensile strength was achieved with the combination of CNT at 15% loading. The results of this study highlight the importance of filler selection in enhancing the mechanical properties of elastomers. Carbon fillers, particularly CNTs, have shown to be effective in improving the tensile strength of elastomeric materials. This has important implications for various industries, particularly in the development of new materials for applications in the automotive and medical fields. The use of elastomers in the automotive industry has become increasingly important due to their ability to absorb mechanical shocks and vibrations. Elastomeric materials have also found applications in the medical field, such as in the development of artificial skin, blood pumps, drug delivery systems, and implants. The use of elastomers in food packaging has also become popular due to their ability to provide a barrier against oxygen and moisture. The use of carbon fillers in elastomeric materials has the potential to significantly enhance their mechanical properties, particularly their tensile strength. This study provides valuable insights into the effects of different carbon fillers on the tensile strength of elastomers, which can help in the development of new materials for various industrial applications

Microstructure Characterization, Mechanical and Wear Behavior of Silicon Carbide and Neem Leaf Powder Reinforced AL7075 Alloy hybrid MMC’s.

The demanding material quality criteria in the automotive and aerospace industries have recently had an impact on the development of lightweight aluminium alloys. The choice and application of metal-matrix composites as structural materials in this context are known to offer a variety of benefits. These benefits include the ability to combine high elastic modulus, toughness, and impact resistance; minimum sensitivity to change in temperature or thermal shock; durability of the surface is good; moisture absorption leads to the potential issue while minimum exposure which leads to environmental degradation; and improved fabricability with conventional metalworking equipment. Aluminium metal matrix composites (AMMCs) are a potential material for advanced structural, aviation, aerospace, marine, and defence applications, as well as for the automotive sector and other related fields, due to their outstanding combination of qualities. The stir casting procedure is used to create an aluminium metal matrix composite (AMMC), which is the most efficient way to do so. In this study, the aluminium alloy 7075 is strengthened using neem leaf powder and SiC. The Vickers hardness examination method is used to govern the hardness of hybrid composites. Eventually, the mechanical and tribological properties of the composites were assessed, and their relationship to the composites' matching microstructure and wear was addressed.   &nbsp

Analyzing Microstructural Features, Surface Topography, and Scratch Resistance of Innovative Nano-Composites Coated with High Velocity Air-Fuel Technology

New developments in thermal spraying processes may offer higher-quality alternatives to hard chrome plating and possibilities for hard chrome plating in a range of coating applications. These include spraying with high-velocity air fuel (HVAF) and new spray consumables. The low operating temperatures and accelerated particle velocity of the HVAF process enable investigation and development of a wide range of novel coating materials and applications. The High-velocity Air Fuel Process' quality and efficiency are primarily due to the broad combustion chamber and axial injection of the feedstock through it, as well as the relatively low combustion temperature of an air-fuel mixture and the low gas velocity that provides enough time for the mild heating of the powder particles. The current work discusses the inventive thermal spray procedure used for SAE 1008 carbon steel, a cost-effective substrate material. All of the compositions that were treated have undergone microstructure investigations. A scratch test is conducted in accordance with ASTM guidelines. Assessment of surface morphology clearly demonstrates the relationship between the evaluated parameters. According to the occurrence, scratch methods such as delamination, cracking, plastic deformation, and elastic deformation are highlighted. However, the findings of the scratch test showed that the samples' scratch resistance increased as the coating thickness rose. In comparison to samples with thinner coating, those with thicker coating demonstrated a stronger resistance to scratching. This is explained by the fact that coatings with a higher thickness and density can support the subsurface more effectively and stop cracks from scattering. This can retain the coating's integrity and stop more damage from occurring, improving scratch resistance. Better scratch resistance was displayed by the samples with denser microstructures and smoother surface morphologies. The outcome is greater scratch resistance because a higher density covering can withstand deformation and fracture better than a lower density layer. This is due to the mechanism of deformation and fracture in the coating material. This improvement in scratch resistance can be due to the composites' increased HVAF coating's hardness and adherence. The findings imply that using an HVAF coating to increase the scratch resistance of new nanocomposites may constitute a successful strategy

Little Higgs model effects in γγ→γγ\gamma \gamma \to \gamma \gamma

Though the predictions of the Standard Model (SM) are in excellent agreement with experiments there are still several theoretical problems associated with the Higgs sector of the SM, where it is widely believed that some ``{\it new physics}'' will take over at the TeV scale. One beyond the SM theory which resolves these problems is the Little Higgs (LH) model. In this work we have investigated the effects of the LH model on \gggg scattering \cite{Choudhury:2006xa}.Comment: Talk given at LCWS06, Bangalore, 4 pages (style files included

Spectroscopic Identification of a Proto-Cluster at z=2.300: Environmental Dependence of Galaxy Properties at High Redshift

We have discovered a highly significant over-density of galaxies at z=2.300+/-0.015 in the course of a redshift survey designed to select star-forming galaxies in the redshift range z=2.3+/-0.4 in the field of the bright z=2.72 QSO HS1700+643. The structure has a redshift-space galaxy over-density of delta_g,z ~= 7 and an estimated matter over-density in real space of delta_m ~= 1.8, indicating that it will virialize by z~0 with a mass scale of ~= 1.4x10^15 M_sun, that of a rich galaxy cluster. Detailed modeling of the spectral energy distribution -- from the rest-far-UV to the rest-near-IR -- of the 72 spectroscopically confirmed galaxies in this field for which we have obtained K_s and Spitzer/IRAC photometry, allows for a first direct comparison of galaxy properties as a function of large-scale environment at high redshift. We find that galaxies in the proto-cluster environment have mean stellar masses and inferred ages that are ~2 times larger (at z=2.30) than identically UV-selected galaxies outside of the structure, and show that this is consistent with simple theoretical expectations for the acceleration of structure formation in a region that is over-dense on large scales by the observed amount. The proto-cluster environment contains a significant number of galaxies that already appear old, with large stellar masses (>10^11 M_sun), by z=2.3.Comment: 7 pages including 3 figures. Accepted for publication in ApJ. Typo correcte

Fractography and Tensile studies on the effect of different carbon fillers reinforced hybrid nanocomposites

The use of elastomers has become increasingly important in a variety of industries, including automotive, medical, and food packaging. The adaptability of elastomers to different mechanical stresses has made them a popular choice for these applications. However, the mechanical properties of elastomers can be further enhanced by adding suitable fillers. In this study, the effects of different carbon fillers, namely carbon black, carbon graphite, and carbon nanotubes, on the tensile strength of elastomeric materials were investigated. Different combinations of plain silicone with varying concentrations of CB, CG, and CNT fillers were prepared using a solution casting method. The concentrations of the fillers ranged from 5% to 15% with an interval of 5%. The tensile strength of each combination was measured, and the results showed that the maximum tensile strength was achieved with the combination of CNT at 15% loading. The results of this study highlight the importance of filler selection in enhancing the mechanical properties of elastomers. Carbon fillers, particularly CNTs, have shown to be effective in improving the tensile strength of elastomeric materials. This has important implications for various industries, particularly in the development of new materials for applications in the automotive and medical fields. The use of elastomers in the automotive industry has become increasingly important due to their ability to absorb mechanical shocks and vibrations. Elastomeric materials have also found applications in the medical field, such as in the development of artificial skin, blood pumps, drug delivery systems, and implants. The use of elastomers in food packaging has also become popular due to their ability to provide a barrier against oxygen and moisture. The use of carbon fillers in elastomeric materials has the potential to significantly enhance their mechanical properties, particularly their tensile strength. This study provides valuable insights into the effects of different carbon fillers on the tensile strength of elastomers, which can help in the development of new materials for various industrial applications

The Physical Nature of Rest-UV Galaxy Morphology During the Peak Epoch of Galaxy Formation

Motivated by the irregular and little-understood morphologies of z ~ 2 - 3 galaxies, we use non-parametric coefficents to quantify the morphologies of 216 galaxies which have been spectroscopically confirmed to lie at redshifts z = 1.8 - 3.4 in the GOODS-N field. Using measurements of ultraviolet (UV) and optical spectral lines, multi-band photometric data, and stellar population models we statistically assess possible correlations between galaxy morphology and physical observables such as stellar mass, star formation rate, and the strength of galaxy-scale outflows. We find evidence that dustier galaxies have more nebulous UV morphologies and that larger, more luminous galaxies may drive stronger outflows, but otherwise conclude that UV morphology is either statistically decoupled from the majority of physical observables or determined by too complex a combination of physical processes to provide characterizations with predictive power. Given the absence of strong correlations between UV morphology and physical parameters such as star formation rates, we are therefore unable to support the hypothesis that morphologically irregular galaxies predominantly represent major galaxy mergers. Comparing galaxy samples, we find that IR-selected BzK galaxies and radio-selected submillimeter galaxies (SMGs) have UV morphologies similar to the optically selected sample, while distant red galaxies (DRGs) are more nebulous.Comment: 26 pages. Accepted for publication in the ApJ. Version with full resolution figures is available at http://www.astro.caltech.edu/~drlaw/Papers/UVmorph.pd