Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10620899 | Acta Materialia | 2006 | 8 Pages |
Abstract
An inert gas atomization technique was employed to produce spray deposits of an Al-18Si-5Fe-1.5Cu (wt.%) alloy. The spray-deposited alloy was subsequently hot extruded with a reduction ratio of 6:1 and extrusion temperature of 480 °C. The microstructural features of the as-spray-deposited and extruded alloys were examined using optical, scanning electron and transmission electron microscopy techniques, and chemical analyses of phases were carried out using energy dispersive X-ray analysis and spectroscopic methods. The microstructure of the spray-deposited alloy revealed the presence of a cellular and plate-like morphology of β-Al5SiFe phase coexisting with δ-Al4Si2Fe phase in contrast to the presence of only δ-Al4Si2Fe phase in atomized powder particles. The formation of the β-Al5SiFe phase is suggested to arise as a result of phase transformation of δ-Al4Si2Fe phase during slow cooling of the spray deposit. The hot extrusion of the alloy resulted in fragmentation of both intermetallic phases and Si into nano-sized particles. The microstructure evolution during spray deposition and hot extrusion of the alloy is discussed.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
A.K. Srivastava, V.C. Srivastava, A. Gloter, S.N. Ojha,