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This paper focuses primarily on the wear behavior observed in AISI4340 steel when machining with a multi-layered coated carbide tool. Numerical and experimental examination is processed out to predict the wear performance of AISI 4340 steel along with its cutting force and temperature. In this process, four layers of different coated material are bonded together to form a multi-layered coated carbide tool. The coated thickness is assessed with the assistance of a Scanning Electron Microscope (SEM). Experimental analysis takes place with a heavy duty lathe machine equipped with an infrared thermometer and force dynamometer. Simulation is performed using DEFORM-2D software to simulate cutting forces and interface temperature, and the output results obtained have been compared with the experimental work. With the help of the SEM image, maximum crater wear depth is evaluated and analyzed. Feed plays a crucial role in increasing the chip interface temperature and cutting force. For varied feed rates, the cutting tool edge radius, depth of cut, and cutting speed are taken as the input parameters. The proposed 2D finite element model provides effective parameter values for reducing wear. Results measured indicate that the output parameter values of interface temperature and cutting force obtained from simulation and experimental investigation match each other with high accuracy. Simulation results for temperature distribution around the tool tip show that a maximum temperature of 654 °C is formed at the feed rate of 0.4 mm/rev, leading to high heat flux. For the feed rate of 0.3 and 0.2 mm/rev, there is not much deviation in heat flux around the tool tip. The maximum temperature around the tool tip is near 527 °C for both 0.3 and 0.2 mm/rev. Simulation results show that the lowest tool wear of 0.001 23 mm was obtained for a feed rate of 0.2 mm/rev, followed by 0.004 25 (0.1 mm/rev), 0.005 09 mm (0.4 mm/rev), and 0.007 14 mm/rev. [ABSTRACT FROM AUTHOR]

Erosion, a major threat to the safety and reliability of piping components, can significantly impact their integrity and functionality. This study employs computational fluid dynamics (CFD) to systematically investigate the erosion behavior of four elbow designs (standard 90- degree elbow, 18-degree gored elbow, 22.5-degree gored elbow, and 30- degree gored elbow) subjected to multiphase air-sand and water-sand flows. Our primary objective is to identify the optimal elbow design that effectively mitigates erosion and enhances the safety and reliability of piping systems. Our findings reveal that the 22.5-degree gored elbow exhibits significantly lower erosion rates compared to other designs, particularly in air-sand flows, making it the superior choice for reducing erosion by up to 32% compared to the standard elbow. However, the standard 90-degree elbow demonstrates greater erosion resistance in water-sand flows. This research contributes valuable insights for selecting the optimal elbow design in multiphase flow, ultimately enhancing the design and longevity of piping systems. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA, Ca10(PO4)6(OH)2)-based porous scaffolds have been widely investigated in the last three decades. HA, with excellent biocompatibility and osteoconductivity, has made this material widely used in bone tissue engineering. To improve the mechano-biological properties of HA, the addition of clay to develop HA-based composite scaffolds has gained considerable interest from researchers. In this study, a cost-effective method to prepare a HA–clay composite was demonstrated via the mechanical mixing method, wherein kaolin was used because of its biocompatibility. Prawn (Fenneropenaeus indicus) exoskeleton biowaste was utilized as a raw source to synthesize pure HA using wet chemical synthesis. HA–clay composites were prepared by reinforcing HA with 10, 20, and 30 wt.% of kaolin via the mechanical mixing method. A series of characterization tools such as XRD, FTIR, Raman, and FESEM analysis confirmed the phases and characteristic structural and vibrations bonds along with the morphology of sintered bare HA, HA–kaolin clay composite, and kaolin alone, respectively. The HA–clay composite pellets, uniaxially pressed and sintered at 1100 °C for 2 h, were subjected to a compression test, and an enhancement in mechanical and physical properties, with the highest compressive strength of 35 MPa and a retained open porosity of 33%, was achieved in the HA–kaolin (20 wt.%) clay composite, in comparison with bare HA. The addition of 20% kaolin to HA enhanced its compressive strength by 33.7% and increased its open porosity by 19% when compared with bare HA. The reinforcement of HA with different amounts (10, 20, 30 wt.%) of kaolin could open up a new direction of preparing biocomposite scaffolds with enhanced mechanical properties, improved wear, and better cell proliferation in the field of bone tissue engineering. [ABSTRACT FROM AUTHOR]

The current work is in continuation of our previous work where we reported changes in the properties of epoxy coatings using two different types of hardener in different stoichiometric ratios. The best results-oriented coating stoichiometry was then taken in this research for further modification with the incorporation of 1, 2 and 3 wt.% micro aluminium (Al) pigments designed for coating carbon steel panels. After 7 d of curing, the coated panels were characterized using X-ray diffraction (XRD), (SEM) scanning electron microscopy, (TGA) thermogravimetric analysis, pendulum hardness, a scratch test and nano-indentation. Electrochemical tests were carried out for various exposure periods of time, i.e., 1 h, 7 d, 14 d, 21 d and 30 d, in a 3.5% sodium chloride (NaCl) solution. For the coatings, we found that the presence of 1% Al provided the highest corrosion resistance after exposure periods in the NaCl solution. We also found that prolonging the immersion time decreases the corrosion resistance after 7 d, but increasing the time of immersion to longer periods (14 d, 21 d and 30 d) enhances the corrosion resistance and reduces the degradation of the coatings. [ABSTRACT FROM AUTHOR]