Enhanced mechanical behaviour and grain characteristics of aluminium matrix composites by cold rolling and reinforcement addition (Rice husk ash and Coal fly ash)

Abstract

Aluminium matrix composites significantly benefit the manufacturing sector due to the high strength-to-weight ratio. However, grain refinement was one of the major problems faced by the research community and also as-cast AA6063 contained eutectic silicon with sharp, long elongated laths that consequently reduces strength and limit their applications. So, the prime novelty of this research work is to refine the grains by performing the cold rolling operation in AA6063 and incorporating rice husk ash and coal fly ash in the AA6063 matrix to break those eutectic laths which attributes to the enhancement of the mechanical properties. Rice husk ash and coal fly ash were chosen because they are economical, possess low density and are available in enormous quantities as solid waste by-products. They contain a substantial concentration of SiO2 and serve as a viable reinforcement for improving the mechanical properties of aluminium composites. In this research, the grain characteristics along with the mechanical properties of aluminium composites reinforced with rice husk ash and coal fly ash, produced by the stir casting technique were investigated. The reinforcements were added in varying concentrations (1.5 and 3.0 wt.%). Six specimens were fabricated of which five were cold rolled. Image J and Origin software was used in evaluating the average grain size of the fabricated alloys and their composites. The results were discussed with the help of grain size distribution and profile plots. Structural and composition studies were done using scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction spectroscopy. Hardness and tensile tests were performed on the fabricated composites. The outcome of this research reveals, AA6063-3 wt.% rice husk ash composite has improved hardness (84HV) and tensile strength (156 MPa). Moreover, the average grain size of 10.52 µm was the main reason for the attainment of enhanced mechanical properties.

Revolutionizing Aluminum-Based Composite Manufacturing: Harnessing Fly Ash and Rice Husk Ash Reinforcement through Stir Casting for Sustainability

“…Precise temperature control within the alloy's solidification range prevented premature solidification, crucial for thorough mixing. Subsequently, a degassing procedure effectively removed trapped gases from the molten composite, preserving its structural integrity [44]. This comprehensive manufacturing process was designed to maintain the alloy's integrity while maximizing the dispersion and alignment of reinforcement particles, ultimately aiming to produce a high-quality composite material suitable for subsequent characterization and analysis.…”

Investigation on mechanical properties of aluminum hybrid matrix composites reinforced with fly ash and titanium diboride using stir casting technique

“…The metal matrix composites with an Aluminium (LM25) matrix are remarkable novel materials with applications in the automotive, aerospace, and transportation sectors [4]. Inclusion of reinforcements in the aluminium (LM25) alloy enhanced the hybrid matrix composites physical and chemical properties of shown by numerous researchers [5,6]. Hybrid metal matrix composites (HMMCs) were attracting the researchers because of their better strength, stiffness, micro deformation resistance, heat/ electrical conductivity and resistance to fatigue.…”

Hybridization of aluminium-silicon alloy with boron carbide and ferrotitanium and the effect on mechanical properties as auto-material

“…However, the infusion of the reinforcement into the metal matrix has eventually led to a reduction in strength at a certain weight proportion (Olaniran et al, 2022a;Ogunbiyi et al, 2023). Moreso, ceramic-reinforced aluminum composites are often limited in hot-cold-cryo rolling and extrusion processes on account of the brittle nature of the particles (Olorunyolemi et al, 2022) The major characteristics that make ferrotitanium an appealing material include an outstanding strengthweight ratio, which has led to ferrotitanium being widely used in the aerospace and petrochemical sectors. Yimal et al (2022) conducted a metallographic analysis and studied the wear behavior of Cu-based FeTi-reinforced composites.…”