Title: The physico-mechanical and morphological characterisation of polycrystalline Al/Al₂O₃ composites at different process parameters

Authors: Anup Choudhury; Jajneswar Nanda; Sankar Narayan Das; Kamalakanta Muduli; Srikanth Bathula

Addresses: Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar-751030, Odisha, India ' Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar-751030, Odisha, India ' Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar-751030, Odisha, India ' Papua New Guinea University of Technology, Lae, Morobe Province, PMB 411, Papua New Guinea ' Papua New Guinea University of Technology, Lae, Morobe Province, PMB 411, Papua New Guinea

Abstract: Polycrystalline compounds consist of erratically oriented grains held together by ionic and covalent bonding. During solid-state sintering, the grain boundary energy obstructs dislocation mobility thereby restricting grain size. Thermomechanical action contributes in fabricating the polycrystalline aluminium metal matrix composite (AMMC). Current article has abridged the combined effects of compacting pressure, temperature and time on physical/mechanical/morphological properties of coarse (75 µm~106 µm) polycrystalline aluminium-alumina powder composite, by fabricating through the powder metallurgy (PM) technique at different percentage of alumina addition to the aluminium matrix. Methods like particle size distribution (PSD), x-ray fluorescence (XRF), and x-ray diffraction (XRD) are used to find the appropriate properties. Various temperature/time sintering curves have been demonstrated, resulting in a higher relative density (RD) of AMMC. Scanning electron microscopy (SEM) is used to display the grain structure at various alumina percentages, which integrates grain boundaries and optimises microhardness and compressive strength at 5 wt% alumina.

Keywords: polycrystalline materials; powder metallurgy; PM; solid-state sintering; microhardness; compressive strength.

DOI: 10.1504/IJMATEI.2024.140198

International Journal of Materials Engineering Innovation, 2024 Vol.15 No.3, pp.242 - 263

Received: 26 Nov 2022
Accepted: 26 Jan 2023
Published online: 29 Jul 2024 *

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