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Analytical versus experimental investigation of physical and mechanical characteristics of stir cast hybrid aluminium nanocomposite

Kumar Dinesh, Singh Satnam, Angra Surjit

Composites Theory and Practice

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2023

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R. 23, nr 3

136--144

EN

Aluminium alloys have good mechanical and physical properties and are lightweight, easy to cast, and simple to machine. Aluminium alloys are widely used in the aviation industry, auto sector, defence sector, and structural industries because of their promising abilities. The fundamental aim of this study was to investigate the mechanical properties and physical characteristics of a stir cast hybrid aluminium nanocomposite reinforced with 1-3 wt.% cerium oxide (CeO2) and graphene nanoplatelets (GNPs). Utilizing SEM, microstructural analysis was carried out. The existence of the elements of the reinforcement in the manufactured nanocomposite specimens was verified using EDAX. With an increase in the reinforcement wt.%, improvements in the mechanical and physical properties were seen. In the hybrid nanocomposites reinforced with 3 wt.% GNPs and 3 wt.% CeO2, a low porosity of 1.06% was observed. The best results for tensile strength, yield strength, and microhardness were 398 MPa, 247 MPa, and 119.6 HV, respectively. The SEM micrographs of the studied materials showed that the reinforcement particles were uniformly dispersed and refined into ultrafine grains.

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Enhanced mechanical properties of in situ aluminium matrix composites reinforced by alumina nanoparticles

Afkham Y., Khosroshahi R. A., Rahimpour S., Aavani C., Brabazon D., Mousavian R. T.

Archives of Civil and Mechanical Engineering

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2018

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Vol. 18, no. 1

215--226

EN

In situ fabrication of metal matrix composites has various advantages such as the formation of clean particle–metal interface with strong bonding. In this study, three types of metal oxides powders (commercial TiO2, commercial ZnO, and recycled Pyrex) were injected into a pure aluminium melt to fabricate in situ aluminium matrix composites. Through chemical reaction this process produces alumina nanoparticles which act as the reinforcing agent. The process steps investigated include liquid-state stir casting at 1123 K followed by a hot rolling process. SEM and FESEM microstructural characterizations, as well as EDAX analysis, were used to determine the reactions, which occurred between the molten aluminium and the metal oxides to form nano alumina particles as the reinforcement. Tensile and microhardness tests were also performed on the rolled composites, to identify the effect of metal oxide type and amount, on the mechanical properties of the produced composites. It was found that using recycled Pyrex crushed powders led to the formation of a uniform distribution and reinforcement of alumina nanoparticles, while fine-micron ZnO and especially TiO2 powders did not uniformly distribute in the melt.

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Effect of h-BN solid nano lubricant on the dry sliding wear behaviour of Al-B4C nanocomposites

Harichandran R., Selvakumar N.

Archives of Materials Science and Engineering

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2016

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Vol. 77, nr 1

5--11

EN

Purpose: In this paper, three composites with different B4C content and fixed h-BN nanoparticles reinforced aluminium composites were fabricated through ultrasonic cavitation assisted casting. The role of the B4C and h-BN nanoparticles content on the mechanical and tribological properties of the aluminium composites was evaluated. This study presents the report on characterizion and evaluation of mechanical properties of h-BN and B4C nanoparticles reinforced aluminium composites. Design/methodology/approach: Al-B4C-h-BN composites are fabricated using stir and ultrasonic cavitation-assisted casting processes. The prepared composites are characterized using X-ray diffraction, Scanning Electron Microscopy and Energy Dispersive Spectroscopy. The dry sliding wear behaviour of the Al-B4C-h-BN composites are investigated using pin-on-disc wear test. Findings: The results of microstructural study reveal that uniform distribution, grain refinement and low porosity in composite specimens. The wear properties of the hybrid nanocomposites, containing 4 wt% B4C and 2 wt. % h-BN, exhibit the superior wear resistance properties as compared to unreinforced aluminium matrix. Practical implications: The interest in use of hexagonal boron nitride nanoparticles (h-BN) as solid nano lubricant for aluminium has been growing considerably due to its self lubricating properties.