Please use this identifier to cite or link to this item:

TitlePhysical modification of intermetallic phases in Al-Si-Cu alloys
Author(s)Barbosa, J.
Puga, Hélder
Oliveira, J.
Ribeiro, S.
Prokic, M.
KeywordsIntermetallic compounds
Electron microscopy
Issue date15-Dec-2014
JournalMaterials Chemistry and Physics
Abstract(s)The effect of applying ultrasonic vibration to the melt during cooling on grain structure, type and morphology of intermetallic compounds in AlSi9Cu3(Fe) alloy was studied, as well as their nucleation mechanism. Detailed intermetallics analysis was performed using a combination of SEM/EDS and XRD techniques in order to obtain the most possible reliable information. Results show that without ultrasonic treatment alpha-Al-17(Fe-3.2, Mn-0.8)Si-2, alpha-Al8Fe2Si, beta-Al9Fe2Si2 and Al2Cu are the intermetallic phases present in the as-cast samples. The application of ultrasonic vibration to the melt during cooling proved to be very effective in converting the alpha-intermetallics with Chinese script morphology to polyhedral crystals, suppressing at the same time the formation of the beta-phase. Moreover, the application of this treatment only changes the morphology of alpha-intermetallics since its stoichiometry remains the same (alpha-Al-17(Fe-3.2, Mn-0.8)Si-2). It was also verified that the application of acoustic energy to the melt promotes the change of alpha-Al grains from dendritic to a more globular structure. The ultrasonic treatment is also effective in promoting the fracture of polyhedral crystals of intermetallic phases, reducing their dimensions and causing their homogenous dispersion in the matrix.
AccessOpen access
Appears in Collections:DEM - Artigos em revistas de circulação internacional com arbitragem científica

Files in This Item:
File Description SizeFormat 
MATCHEMPHYS-D-14-00264.pdf2,72 MBAdobe PDFView/Open

Partilhe no FacebookPartilhe no TwitterPartilhe no DeliciousPartilhe no LinkedInPartilhe no DiggAdicionar ao Google BookmarksPartilhe no MySpacePartilhe no Orkut
Exporte no formato BibTex mendeley Exporte no formato Endnote Adicione ao seu ORCID