Investigating the Microstructural and Mechanical Properties of Novel Ternary Reinforced AA7075 Hybrid Metal Matrix Composite

Abstract

This study investigates the comparison of the microstructural and mechanical properties of a novel ternary reinforced AA7075 hybrid metal matrix composite. Four samples, including AA7075 (base alloy), AA7075-5wt %SiC (MMC), AA7075-5wt %SiC-3wt %RHA (s-HMMC), and AA7075-5wt %SiC-3wt %RHA-1wt %CES (n-HMMC) were developed using the stir casting liquid metallurgy route, followed by the heat treatment. The experimental densities corresponded with the theoretical values, confirming the successful fabrication of the samples. A minimum density of 2714 kg/m3 was recorded for the n-HMMC. In addition, the highest porosity of 3.11% was found for n-HMMC. Furthermore, an increase of 24.4% in ultimate tensile strength and 32.8% in hardness of the n-HMMC was recorded compared to the base alloy. However, its ductility and impact strength was compromised with the lower values of 5.98% and 1.5 J, respectively. This was confirmed by microstructural analysis, which reveals that n-HMMC has mixing issues and forms agglomerates in the matrix, which served as the potential sites of stress concentration leading to low impact strength and ductility. Nevertheless, the hybrid composites showed superior mechanical properties over the MMC and its base alloy.

Enhancing the Mechanical Properties of AZ31D Alloy by Reinforcing Nanosilicon Carbide/Graphite

“…The densities of the four specimens are illustrated in Table 3. The density of nanocomposites increased with decreased porosity as the increase particulates [24]. Here, the measured density was lower values as compared with the theoretical density due to the dispersion of atoms in the nanocomposite, as is represented in Figure 8.…”

“…The rule of the mixture method was applied to calculate the samples theoretical density using Equation (2). The percentage porosity of specimens was calculated using Equation (3) [24].…”

“…Another reason was the reinforcements overstrained the lattice. The grain size of the reinforcements bonding between the reinforcements and matrix may affect the composite's strength [24,29]. The increased weight fractions of reinforcement will lead to enhance in the mechanical properties of S2 and S3 nanocomposites.…”

Hardness and corrosion behaviour of stir cast LM26 Al/sugar palm fibre ash composites

“…The reliance on these synthetic reinforcement importations from overseas, combined with the high cost of foreign exchange, infers that synthetic reinforcements purchased locally are relatively expensive if available. Researchers have shown keen interest in improving the mechanical characteristics of AMCs by incorporating inexpensive and green reinforcements (Khan et al, 2022). Green agrarian wastes are readily available, environmental-friendly, and assets as renewable energy in today's world (Armynah et al, 2018).…”