Advances in fabrication of ceramic corundum abrasives based on sol–gel process

The aim of the present study is to investigate the effect of Si and SiC addition on the microstructure, mechanical, and corrosion properties of Al matrix-based composites. Al–Si (2 wt% fixed) alloy...

Microstructural, mechanical and corrosion behaviour of Al─Si alloy reinforced with SiC metal matrix composite

Artificial intelligence systems for tool condition monitoring in machining: analysis and critical review

Studying on the anode materials with high energy densities for next-generation lithium-ion batteries (LIBs) is the key for the wide application for electrochemical energy storage devices. Ti-based compounds as promising anode materials are known for their outstanding high-rate capacity and cycling stability as well as improved safety over graphite. However, Ti-based materials still suffer from the low capacity, thus largely limiting their commercialized application. Here, we present an overview of the recent development of Ti-based anode materials in LIBs, and special emphasis is placed on capacity enhancement by rational design of hybrid nanocomposites with conversion-/ alloying-type anodes. This review is expected to provide a guidance for designing novel Ti-based materials for energy storage and conversion.

Recent progress in Ti-based nanocomposite anodes for lithium ion batteries

In the present work, the effect of aging temperature and particle size ratio of SiC particles on the mechanical and tribological properties of A357 composites reinforced with dual particle size SiC were investigated. The composites were prepared by melt-stirring assisted permanent mold casting technique with different weight fractions (3% coarse +3% fine, 4% coarse +2% fine, and 2% coarse +4% fine) of large and small size SiC particles. These three prepared composites are referred as DPS1, DPS2 and DPS3 composites. The solutionizing temperature was maintained constant at 540 °C for 9 h while the aging was done at 160 °C, 180 °C and 200 °C (T6 treatment) for 6 h. Optical and scanning electron microscopy studies showed fairly uniform dispersion of dual size SiC particles in A357 matrix with good interfacial bonding. High-resolution transmission electron microscopy images showed formation of uniformly dispersed needle-like β″ phase and spherical shaped β-Mg2Si precipitates under peak aging conditions. Compared to T6 treated A357 alloy, the T6 treated DPS A357 composites showed improved yield strength, tensile strength, hardness and wear resistance. Among the three composites, hardness and wear resistance of T6 treated DPS2 composite was found to be significantly higher when compared to the other two composites (DPS1 and DPS3). Ratio of large particles to small particles also seems to effect the mechanical and tribological properties. Presence of more small particles was found to be good for strength and ductility whereas more large particles were found to be good for hardness and wear resistance.

The effect of heat treatment on the mechanical and tribological properties of dual size SiC reinforced A357 matrix composites

Most mechanical systems (in particular, gear transmission system) undergo relative motion which results in increased friction phenomenon (friction coefficient, stresses, and wear rate) and thereby results in loss of efficiency. Mechanical parts undergo relative motion in different geometry configurations and orientations that induce a different state of stress as a result of friction. Till date, attempts are being made to minimize the friction with full sphere pin geometry configuration. The present work focused to reduce the frictional and wear rate, and experiments are conducted with tribo-pairs. i.e., nickel-coated pin surface slide against Al6061 alloy disc. The friction studies are carried out at different loads and geometries of pin surfaces (sphere and hemisphere configured at different orientations such as full sphere and hemisphere configured at 0°, 45°, and 90°) to induce different stress states with reference to sliding directions. Change in the geometry of EN8 pin material and their orientation with reference to sliding direction resulted in a different state of stress. The resulting stress levels were examined under the scanning electron microscope, which revealed the mechanisms of adhesion, abrasion, and extrusion. At a lower magnitude of orientation and load, the extent of asperity breaking lessens and material removal from pin surface decreases. Abrasion wear mechanism was observed corresponding to full sphere configuration on Al 6061 disc, whereas adhesive wear mechanisms are seen with hemisphere pins. The amount of aluminum transfer on pin surface with a hemisphere pin is comparatively more than that of full sphere configuration. At a lower magnitude of state of stress, the mechanism of sliding was dominated by the adhesion effect. At a higher level of state of stress, the mechanism of sliding was dominated by abrasion and extrusion.

Effect of Pin Geometry and Orientation on Friction and Wear Behavior of Nickel-Coated EN8 Steel Pin and Al6061 Alloy Disc Pair

Increased material demand in all sectors is primarily due to exponential growth in population to fulfill human needs and comforts. Recycling of collected aluminium beverage cans and Al 6061 alloy scraps from industries ensures energy savings with reduced environmental problems in fabricating composite parts economically. The iron oxide (α-Fe2O3) nanoparticles were prepared by precipitation method using ferric chloride and ammonia as a precursor. The prepared nanoparticles were characterized by using Transmission Electron Microscope (TEM), X-Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR). Stir cast processing route ensures uniform mix of reinforcement nanoparticles in matrix material. The prepared nanocomposites (matrix: Al Scrap (90% Scrap Al 6061 alloy + 10% Waste Al can); reinforcement: 2%, 4% and 6% wt. of Al matrix) were mechanically characterized for hardness and tensile strengths. It was observed that, increased percent of Fe2O3 nanoparticles in the metal matrix nanocomposite (MMCs) resulted in significant increase in hardness and tensile strength values. Fractography analysis examined viz. scanning electron microscope (SEM) revealed a ductile failure for as-cast Al scrap followed by brittle failure in Al MMC's.

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Synthesis and Characterization of Fe2O3 Nanoparticles Reinforced to Recycled Industrial Aluminium Scrap & Waste Aluminium Beverage Cans for Preparing Metal Matrix Nanocomposites

The present work focuses on the mold design and production of the multifunctional device laryngoscope with surface quality through the injection molding process. A laryngoscope is a device used by anesthesiologists to lift the tongue that facilitates to fix the air pipe in the larynx. Demand still exists in the laryngoscope part to assist anesthesiologists to take care of the airway without causing chest compression and ensure visualization of vocal cords. Therefore, the present work aims at developing a laryngoscope with a double channeled device, wherein one for aligning the camera and another for the air pipe. The paper outlines the design parameters required for manufacturing a single cavity mold to produce a laryngoscope viz. injection molding machine. The mold has multiple plates with complex fluid channels which ensures effective thermal management in-mold system. The mold is manufactured using high-strength tool steel materials and the product laryngoscope (ABS: Acrylonitrile butadiene styrene) is fabricated from the designed mold. Taguchi L9 experimental array was used to determine the optimal conditions (injection pressure, injection velocity, mold and melt temperature) for desired surface finish in the laryngoscope parts. The designed mold and optimized injection molding conditions resulted in a lower surface roughness value equal to 0.214 µm. Thereby, injection-molded laryngoscope parts can be used for large-scale productions for the benefit of medical applications.

Design and Fabrication of Injection Molds to Manufacture Double Channel Laryngoscope for Effective Airway Management: Taguchi Method for Surface Roughness Optimization

Avinash Lakshmikanthan

Papers

Effect of Pin Geometry and Orientation on Friction and Wear Behavior of Nickel-Coated EN8 Steel Pin and Al6061 Alloy Disc Pair

Synthesis and Characterization of Fe2O3 Nanoparticles Reinforced to Recycled Industrial Aluminium Scrap & Waste Aluminium Beverage Cans for Preparing Metal Matrix Nanocomposites

Design and Fabrication of Injection Molds to Manufacture Double Channel Laryngoscope for Effective Airway Management: Taguchi Method for Surface Roughness Optimization

Effect of interlock angle and bottom die flange diameter on clinching joint load bearing capacity in cross-tensile loading

Investigation of High-Temperature Erosion Behavior of NiCrAlY/TiO2 Plasma Coatings on Titanium Substrate