Akademik Veri Yönetim Sistemi
11th International Azerbaijan Congress on Life, Engineering, Mathematical, and Applied Sciences, Baku, Azerbaycan, 21 - 22 Haziran 2025, cilt.1, ss.472-475, (Özet Bildiri)
In this study, the effect of T6 heat treatment parameters on the mechanical behavior and microstructural evolution of 6XXX series aluminum alloys with different recycled content ratios was investigated.
Two casting series, Series A with high recycled content and Series B with low recycled content, were investigated.
In the direct cooling casting process, after homogenization and extrusion processes, artificial aging was applied to the samples at 150° C, 175° C and 200° C for 2.5, 5 and 8 hours.
Optical microscope examination and mechanical tests (tensile and hardness) were carried out to evaluate the changes in grain morphology, precipitation behavior and mechanical performance.
The results show that Series A forms a Fe-rich spherical intermetallic structure due to its higher Mn/Fe ratio (~0.27) and therefore increases ductility.
In contrast, Series B, which has a lower Mn content (~0.06), was observed to contain needle-like β-Fe intermetallic structures that reduce ductility.
In addition, Series B contains approximately twice as much Cu as Series A.
This increased the precipitation kinetics and early strength; however, it caused excessive aging, especially at 200° C, with the coarsening of Mg2Si precipitates.
Optical micrographs confirmed that these precipitates grew under excessive aging conditions and were associated with mechanical failures.
Series A, on the other hand, maintained its strength with its more stable intermetallic morphology and structure that is less prone to excessive aging.
The results of the study emphasize the importance of alloy chemistry and heat treatment design to optimize the performance of recycled aluminum alloys.
The balance between strength mechanisms and microstructural stability is critical to achieving the targeted mechanical performance in sustainable aluminum applications.
Keywords: 6XXX series recycled aluminum alloys, T6 heat treatment, Mg2Si precipitates, intermetallic phases, mechanical properties