Investigation of the Mechanical properties of Mica Reinforced Aluminum Alloy

Abstract

Aluminium alloy 6063 was reinforced with natural mica (muscovite) to fabricate metal–matrix composites (MMCs) via the stir casting process. Four compositions (0, 5, 10, and 15 wt% mica) were produced. Specimens were polished and etched for optical microscopy, and hardness was measured (Brinell HLB test). Results show that pure Al6063 had the highest hardness (~119 HLB), which decreased with mica addition up to 10% (to ~91 HLB) and then partially recovered at 15% (107 HLB). Optical micrographs indicated a relatively uniform dispersion of mica flakes throughout the matrix (no severe agglomeration), confirming effective stirring. The non-monotonic hardness trend is attributed to dispersion and interfacial bonding issues: at low mica content, weak metal–mica bonding and voids reduce load transfer (lower hardness), while at higher loadings (15%), particle packing improves, enhancing hardness. These results advance understanding of mica as an Al reinforcer. Improved wear resistance and strength-to weight ratio are anticipated, suggesting potential applications in automotive and aerospace components where weight reduction and durability are critical.