Conception, Production, and Characterization of Al-Mg-Si (6xxx) Alloys Contaminated with Iron During Recycling and Modified with Nickel for Upcycling

• Grant number: 24/23186-7
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: September 01, 2025
• End date: August 31, 2029
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: José Eduardo Spinelli
• Grantee: Argos Soares Silva
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated research grant: 23/06107-3 - Study of the growth of AlFe primary phases in Al alloys and of intermetallic layers in Sn-Bi-X/copper joints, AP.R

Abstract

In the recycling of 6xxx series Al alloys, the accumulation of residual impurities, particularly Fe,leads to the formation of coarse intermetallic compounds during solidification, such as the ¿-Al5FeSi phase. These compounds compromise mechanical properties, hindering the efficientreuse of scrap materials. As an alternative to reducing Fe content, manipulating the morphology,size, and distribution of intermetallics is a viable strategy to mitigate their deleterious effects. Inthis context, adding Ni to recycled alloys can induce the formation of more compact intermetallicphases, such as Al9FeNi, reducing anisotropy and improving ductility and mechanical strength.In this project, analyses will be conducted to understand the effects of Ni on Al-1%Si-0.7%Mgalloys contaminated with Fe. The project steps will include: i) controlled solidification underdifferent cooling conditions, ii) homogenization heat treatments at 490 °C and 530 °C forvarying durations, and iii) hot and cold rolling to evaluate microstructural transformations andmechanical properties. The techniques to be employed include X-ray computed tomography(XCT), scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), andmechanical testing. The main objectives are: i) to transform ¿-Al5FeSi intermetallics into ¿-Al15(Fe,Mn)3Si2 phases that are more favorable to ductility, ii) to evaluate the influence ofdifferent cooling rates and Ni concentrations on the morphology of intermetallic phases, and iii)to correlate microstructural changes with mechanical properties. It is expected that the resultswill contribute to advancing recycling and upcycling routes for Fe contaminated Al alloys,promoting more sustainable and effective solutions for the materials industry. (AU)