Directional Solidification of Sn-Cu6Sn5 In Situ Composites
Author
Source
Advances in Materials Science and Engineering
Issue
Vol. 2019, Issue 2019 (31 Dec. 2019), pp.1-8, 8 p.
Publisher
Hindawi Publishing Corporation
Publication Date
2019-03-13
Country of Publication
Egypt
No. of Pages
8
Abstract EN
The Sn-Cu system presents an important interest from academic and technological point of view because it is part of the family of alloys proposed as lead-free solder alloys for electronic components and also due to the mechanisms involved during the growth of the different phases.
Sn-Cu system has two intermetallic phases, i.e., ε-Cu3Sn and η-Cu6Sn5, and η can be used as the negative (anode) electrode in Li-ion batteries, alone or as part of (Co,Ni)xCu6−xSn5-type composites.
Obtaining this η phase from liquid with the appropriate chemical composition is a very difficult task because it has a formation temperature lower than liquidus for such a composition.
In this way, the η phase appears as a consequence of a solid-solid transformation from the ε phase However, it is possible to find the η phase as the primary or secondary phase after a eutectic reaction for lower concentrations of Cu.
On the other side, the Cu6Sn5 phase shows a hexagonal to monoclinic solid-solid transformation around 187°C, which could affect the mechanical system stability when it is used as solder.
In this work, directional solidification at different growth velocities of hypereutectic Sn-Cu samples was performed.
The resultant microstructure varies with the growth velocity, but it is formed for a fibber-like primary phase Cu6Sn5 which is projected towards the liquid phase.
Behind this region, these fibbers are rounded by a two-phase Sn-Cu6Sn5 structure.
In this way, three zones could to be defined in the sample during the directional growth: (i) an entirely solid two-phase region, formed by η rounded by β(Sn) + η eutectic-like structure, (ii) a two-phase solid (η) + liquid, and (iii) the remnant liquid in front of the interface.
American Psychological Association (APA)
Fornaro, Osvaldo. 2019. Directional Solidification of Sn-Cu6Sn5 In Situ Composites. Advances in Materials Science and Engineering،Vol. 2019, no. 2019, pp.1-8.
https://search.emarefa.net/detail/BIM-1121265
Modern Language Association (MLA)
Fornaro, Osvaldo. Directional Solidification of Sn-Cu6Sn5 In Situ Composites. Advances in Materials Science and Engineering No. 2019 (2019), pp.1-8.
https://search.emarefa.net/detail/BIM-1121265
American Medical Association (AMA)
Fornaro, Osvaldo. Directional Solidification of Sn-Cu6Sn5 In Situ Composites. Advances in Materials Science and Engineering. 2019. Vol. 2019, no. 2019, pp.1-8.
https://search.emarefa.net/detail/BIM-1121265
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references
Record ID
BIM-1121265