Additive Manufacturing technology can now speed up and improve the accuracy of the manufacturing process. Manufacturing products with 3D Metal printing gets simpler, quicker, and more precise. Recent ...studies showed that 3D metal printing with the type laser powder bed fusion (LPBF) could produce primary air fans (PAF) for industrial applications with a quality that can be compared with the existing model. LPBF manufacturing process showed errorless and had advantages compared with the traditional process, allowing the development of precise 3D shapes and sizes. The penetration tests with visual inspection revealed that the 3D printed product has no surface defects. The surface roughness test showed that the specimen has a slightly more refined surface than the original product. The chemical test showed that 3D metal printing materials resemble original model materials, with Aluminium 89.6% wt. and Silicon 9.57% wt., while other elements are less than 1%. The average hardness of 3D material metal printing is 91.6 HV, while the original model material is 106.03 HV. Scanning Electron Microscope-Energy Dispersive X-Ray (SEM-EDX) tests indicate that the oxide that forms is Al2O3.
SDN's ability to provide a global view, centralized control, and flexibility in orchestrating network infrastructure are expected to overcome challenges in the dynamic conditions of vehicular ...communications. We are looking to rely on SDN technologies to achieve Vehicular communications capacity and performance, which increase the safety of vehicles and transportation, save cost & energy, and increase the vehicles' autonomy level. The usage of SDN in vehicular communications has been the subject of considerable research. Researchers address challenges such as low latency, high throughput, reliability, dense VANET, security, and scalability. Furthermore, this paper surveys the integration of SDN and other enabling technologies with vehicular communications, both for IEEE 802.11 and the C-V2X RAT families. It begins by discussing performance comparisons and coexistence between IEEE 802.11 and C-V2X standards, implementation of SDN in various use cases, integration of SDN with other enabling technologies, the study of particular SDN components to support vehicular communications performance, and SDN usage to support the specific issues vehicular communications. Finally, open directions and challenges of the research are discussed.
Weight plays a significant role in the automotive and aerospace fields due to the demand of lightweight material structures. A lighter body in weight (BIW) and in structure can reduce fuel ...consumption, lessen emissions, and support the SDGs 9, 11, 12, and 13. Therefore, polyurethane (PU) foam is suitable for applications that require low weight. The characteristics of hybrid polyurethane-graphite micro were successfully evaluated in this study. Several tests have been used to characterize these structures, such as, compression, hardness, density, surface evaluation, and FTIR analysis. The results showed that the expansion and shrinkage variations lead to different shapes at specific ratios. Compression tests show that the highest value occurred at 0.84 kN, with a 4:1 ratio found in pure PU foam without any reinforcement. PU foam with 2% graphite filler showed the highest results at the 4:1 ratio with a value of 0.45 kN. Furthermore, the highest hardness test result was 37.7 SHD. Density testing indicates that the highest value is obtained from specimens with a 4:1 ratio of 0.077 g/cm3. FTIR testing reveals that adding graphite as a filler alters the chemical bonds during the formation of solid PU foam. Surface observations show that adding graphite as a filler influences the variation in material structure formation. All the evaluation has tended to conclude the present combination as suitable for lightweight structures applications.
The development of high-entropy alloys (HEAs) for high-temperature applications has been driven by the limitation of nickel-based superalloys in achieving optimal efficiency at higher temperatures ...for higher efficiency in power generation engines. The alloys must have high oxidation resistance and microstructural stability at high temperatures. Relatively equimolar multi elements involved in HEAs produce microstructure containing a single solid solution or multiphase that improves the mechanical properties and oxidation resistance resulting from sluggish diffusion and core effects. In this study, the oxidation behavior and microstructural changes of Al0.75CoCrFeNi HEA at 900, 1000, and 1100 °C in air atmosphere were investigated. Based on the XRD and SEM-EDS analysis, the mechanism of oxide scale formation and microstructural changes of the substrate are proposed. The results show that the oxidation behavior of the alloy follows a logarithmic rate law. Different oxide compounds of CoO, NiO, Cr2O3, and CrO3, θ-Al2O3, α-Al2O3, and Ni(Cr,Al)2O4 with semicontinuous oxides of Al2O3 with Cr2O3 subscale and an oxide mixture consisting of spinel of Ni(Cr,Al)2O4 and Co(Cr,Al)2O4 were found. During oxidation, Widmanstätten of FCC-A1 and BCC-B2/A2 phases in the substrate have changed. Spheroidization of B2 and a reduction in volume fraction decrease the hardness of the substrates.
High-temperature operation, such as in gas turbine engines, is typically limited by the ability of materials to withstand extreme operating conditions. The need for a combination of high-temperature ...strength and oxidation resistance, as well as microstructural stability, has led to the continued use of nickel-based superalloys as materials for turbine blades, the most critical component in aero gas turbine engines. Due to their limited melting points, materials beyond superalloys are needed to meet increasing fuel efficiency requirements. High entropy alloys have recently been considered as candidates for materials to replace nickel-based superalloys. This paper discusses the microstructures and high-temperature oxidation behavior of Al 0.75 CoCrCuFeNi high entropy alloy at 900, 1000, and 1100°C. It was found that the oxidation rate constants for Al 0.75 CoCrCuFeNi oxidized at 900, 1000, and 1100°C are 3.84 x 10 -10 , 5.99 x 10 -10 , and 8.97 x 10 -10 (mg/cm 2 .s), respectively, with an activation energy for oxidation of 66.58 kJ/mol.
The technology development of electrochemical energy storage devices including lithium-ion battery is urgently needed to support the increased demand for renewable energy and production growth of ...portable electronic devices. Extensive research on nanostructural engineering aims to improve battery performance in terms of capacity, energy density, cycling ability, and Coulombic efficiency. This review describes the concept of atomic layer deposition (ALD) and focuses on ALD for Li-ion battery. Within the last few years, interest in the nanostructured materials synthesized by ALD to enhance battery performance has rapidly improved. Given the urgent requirement for reliable materials for high battery performance, ALD is a robust method for developing and fabricating nanostructure materials for next-generation Li-ion batteries, especially in the design of anode and cathode electrodes of the batteries.
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