Effect of rare-earth (La, Ce, and Y) additions on the microstructure and mechanical behavior of Sn-3.9Ag-0.7Cu solder alloy

M. A. Dudek, Nikhilesh Chawla

Research output: Contribution to journalArticlepeer-review

38 Scopus citations

Abstract

In this article, we report on the microstructure and mechanical properties of Ce- and Y-containing Sn-3.9Ag-0.7Cu solders. The microstructures of both as-processed solder and solder joints containing rare-earth (RE) elements (up to 0.5 wt pct) are more refined compared to conventional Sn-3.9Ag-0.7Cu, with decreases in secondary Sn dendrite size and spacing and a thinner Cu 6Sn5 intermetallic layer at the Cu/solder interface. These results agree well with similar observations seen in La-containing solders reported previously. The monotonic shear behavior of reflowed Sn-3.9Ag-0.7Cu-X(Ce, Y)/Cu lap shear joints was studied as well as the creep behavior at 368 K (95 °C). The data were compared with results obtained for Sn-3.9Ag-0.7Cu and Sn-3.9Ag-0.7Cu-XLa alloys. All RE-containing alloys exhibited creep behavior similar to Sn-3.9Ag-0.7Cu. Alloys with Ce additions exhibited a small decrease in ultimate shear strength but higher elongations compared with Sn-Ag-Cu. Similar observations were seen in La-containing solders. The influence of the RE-containing intermetallics (CeSn3 and YSn3) that form in these alloys on the microstructural refinement, solidification behavior, and mechanical performance of these novel materials is discussed.

Original languageEnglish (US)
Pages (from-to)610-620
Number of pages11
JournalMetallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
Volume41
Issue number3
DOIs
StatePublished - Mar 1 2010

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Mechanics of Materials
  • Metals and Alloys

Fingerprint Dive into the research topics of 'Effect of rare-earth (La, Ce, and Y) additions on the microstructure and mechanical behavior of Sn-3.9Ag-0.7Cu solder alloy'. Together they form a unique fingerprint.

Cite this