Influence of Nanoparticles Reinforcements on Aluminium 6061 Alloys Fabricated via Novel Ultrasonic Aided Rheo-Squeeze Casting Method

Abstract

This study emphasis on a novel fabrication technique to fabricate hybrid cermets using Al 6061 alloy with nano sized SiC, Al2O3 and TiO2 as reinforcements. During the fabrication process, the melted pool was ultrasonicated to disperse nanoparticles at 20 kHz for 5 min and pressure of 50 MPa was applied to eliminate voids. The influence of nanoparticles on physical, thermal and mechanical properties were evaluated by tensile, wear and thermal studies. Cermets with Al2O3 reinforcements showed higher mechanical performance compared to Al alloy. This enhancement could be related to the uniform distribution of Al2O3 with refinement in grain size of Al alloy which was observed via surface analysis. The morphological studies provided justifiable evidence of homogeneous distribution, nominal cluster along with agglomeration and cavities shrinking on the cermets. The agglomeration of nanoparticles along with SiC protected the cermet in corrosion and abrasive wear by ~ 97% and ~ 71%. The study evidenced the novel fabrication method using ultrasonic rheo-squeeze casting led to improvement in mechanical and thermal properties of the hybrid cermets. Graphical abstract

Multi-walled carbon nanotubes (MWCNTs)-reinforced ceramic nanocomposites for aerospace applications: a review

“…Nanocomposites have initiated a revolution of replacing the traditional alloys on the automobile composites [130,131]. Steel-based components on automobiles provided high corrosion resistance and strength, but for high-performance vehicles, there is a need to reduce the weight/power ratio.…”

“…This allows the ceramics to act as possible replacement in automobile applications by providing with hardness, lightweight and high temperature capabilities. Reinforced ceramics have potential to be used in engine parts, brake discs, valves, cylinder liners, spark plug, sensors, isolators, filters and pistons-all are subjected to higher load and wear which could lead to deformation and wear and are examples where ceramic-based nanocomposites could be efficient [130,131]. Along with the load bearing capabilities, wear is also an important factor in the automobile and industrialscale applications.…”

“…Though, aluminium and its alloys are extremely popular in automobile applications for inner surfacing and ducting. Nowadays, aluminium-based metal matrix with ceramic reinforcements has also created new roles in automotive materials [130,131]. Nayim et al examined stir cased aluminium matrix composite reinforced with CNTs/ TiC and reported a reduction in the density and increase in hardness due to the volatile nature of reinforcing material [134].…”

“…For example, ceramic materials have significant advantages in high-temperature applications. Various ceramics have been studied for its suitability in the thermal barrier coatings, structural areas and as reinforcements [32,130,131]. However, due to the lower fracture toughness and unable to satisfy required strength, ceramics require a potential reinforcement for its utilisation in aerospace industries.…”

An investigation on microstructure and mechanical behaviour of aluminium hybrid metal matrix nanocomposite fabricated through electromagnetic stir casting process

“…Whereas, the hybrid cermets overall properties were also influenced with the fabrication methods allied by the alloys [18,19,20]. Numerous casting techniques like stir casting, squeeze casting, compo casting, etc., are more usually used for the production of hybrid cermets which involves the molten base metal as intermediate [21,22]. The amalgamation of oxide particles into molten base metals causes nonuniform dispersion, aggregation, and formation of cluster powders on surfaces [23].To overcome this problem electromagnetic stirrers were further utilized.…”