Study of Thermal and Mechanical Properties in Al-Mg Alloys for Lightweight Thermal Applications

Abstract

Aluminium and Magnesium alloys are highly valuable due to their mechanical strength, corrosion resistance, and machinability, making them ideal for lightweight applications in aerospace and automotive thermal systems. This study investigates the thermal and mechanical behaviour of aluminium-magnesium (Al-Mg) alloys with varying magnesium content. Two alloy compositions Al 90% + Mg 10% (Sample 1) and Al 80% + Mg 20% (Sample 2) were analysed using a guarded hot plate apparatus for thermal conductivity, Brinell hardness testing, tensile strength measurement, and optical microscopy for microstructural evaluation. Results showed that Sample 1 exhibited higher thermal conductivity due to a finer and more uniform microstructure, while Sample 2 demonstrated superior mechanical properties such as higher hardness and tensile strength, attributed to solid solution strengthening and refined grain structure. Microstructural analysis revealed that increased magnesium content promotes grain refinement and precipitate formation, affecting both heat transfer and mechanical performance. The findings highlight the critical role of alloy composition and microstructure in tailoring Al-Mg materials for lightweight thermal and structural applications.