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This research investigates the mechanical properties improvement of reinforced Al6061 using powder metallurgy (PM) route. It utilizes the nanoparticles strengthening mechanism to enhance the prepared samples' mechanical properties. For this purpose, Silver Nano-Particles (AgNPs) with contents of 0 wt%, 1 wt%, and 2 wt% were used to reinforce the Al6061 Matrix Composition (AMC). For optimization purposes, many parameters have been considered during the research journey namely: compaction pressure, sintering temperature, dwelling time, and reinforcement contents. All samples are examined in terms of density, hardness, and compression strength. Additionally, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, mapping analysis, and XRD were used to investigate the microstructure. The experimental results revealed highest hardness values at 2 wt% AgNPs reinforced sample that was sintered at 600 °C, while the lowest was obtained at un-reinforced sample sintered at 550 °C. Furthermore, the compression strength of sample reinforced with 2 wt% AgNPs and sintered at 600 °C recorded an improvement of 25.8% of the maximum compression strength compared to the un-reinforced sample, as it reached 216 N/mm2. Regarding microstructural analysis, SEM imaging and EDX played an important role in exploring and interpreting many unusual test behaviors including the formation of intermetallic bonding, minor pores formation, and reinforcement dispersion un-homogeneity. [ABSTRACT FROM AUTHOR]

This research investigates the mechanical properties improvement of reinforced Al6061 using powder metallurgy (PM) route. It utilizes the nanoparticles strengthening mechanism to enhance the prepared samples' mechanical properties. For this purpose, Silver Nano-Particles (AgNPs) with contents of 0 wt%, 1 wt%, and 2 wt% were used to reinforce the Al6061 Matrix Composition (AMC). For optimization purposes, many parameters have been considered during the research journey namely: compaction pressure, sintering temperature, dwelling time, and reinforcement contents. All samples are examined in terms of density, hardness, and compression strength. Additionally, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, mapping analysis, and XRD were used to investigate the microstructure. The experimental results revealed highest hardness values at 2 wt% AgNPs reinforced sample that was sintered at 600 °C, while the lowest was obtained at un-reinforced sample sintered at 550 °C. Furthermore, the compression strength of sample reinforced with 2 wt% AgNPs and sintered at 600 °C recorded an improvement of 25.8% of the maximum compression strength compared to the un-reinforced sample, as it reached 216 N/mm2. Regarding microstructural analysis, SEM imaging and EDX played an important role in exploring and interpreting many unusual test behaviors including the formation of intermetallic bonding, minor pores formation, and reinforcement dispersion un-homogeneity. [ABSTRACT FROM AUTHOR]

Cu–Ni/Al 2 O 3 nanocomposite powders were manufactured using an in situ chemical reaction technique. This technique provides improved wettability and adhesion between the matrix and reinforcement phases. Aluminum nitrate, copper nitrate and nickel nitrate were used as start materials for the production of the composites. The powders were sintered in a hydrogen environment at 900 °C for 2 h after being cold pressed at 700 MPa. To determine the effect of Al 2 O 3 on electrical and thermal conductivities and thermal expansion behaviors, the Cu–Ni matrix was supplemented with 3, 5, and 8 wt% Al 2 O 3. The findings revealed that Al 2 O 3 nanoparticles (20 nm) were dispersed uniformly throughout the copper-nickel matrix. Microhardness was improved from 53.3 HV for Cu–Ni matrix to 92.7 HV for Cu–Ni/8%Al 2 O 3 nanocomposites. The electrical and thermal conductivities and thermal expansion coefficient were reduced as the amount of Al 2 O 3 in the Cu–Ni matrix increased. The electrical conductivity was reduced by 38.7% by addition 5% Al 2 O 3 nanoparticles to Cu–Ni matrix. The high interfacial bonding between Cu–Ni and Al 2 O 3 nanoparticles was the main reason of the hardness improvement and maintaining relatively good electrical and thermal properties. [ABSTRACT FROM AUTHOR]

Chemical-based synthesis of co-formed oxide (CuO–NiO–Al 2 O 3) nanoparticles, followed by selective hydrogen reduction of the Cu and Ni oxides and ultimately consolidation into pellets, produced various compositions of Cu–Ni/Al 2 O 3 nanocomposites. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy analyses were used to characterize the powders. The generated powders ranged in size from 20 to 70 nm, with a considerable presence of agglomerates. According to SEM examination, the powders were homogeneous in shape and particle size. Cold pressed nanocomposite powders were sintered for 2 h at 950 °C. SEM with energy dispersive spectroscopy (EDS) was also used to study the microstructure of the sintered specimens. In addition, the physical and mechanical properties of sintered specimens were studied. When the Al 2 O 3 content increased, a more uniform distribution of nanosized Al 2 O 3 particles in the Cu–Ni matrix was attained, resulting in a reduction in particle size. The results also demonstrated that as the Al 2 O 3 concentration was raised, the microhardness and compressive strength of the nanocomposites rose by 74% and 67% compared to pure alloy, with the exception of fracture strain, which decreased dramatically. [ABSTRACT FROM AUTHOR]