エレクトロニクス実装学会誌
Online ISSN : 1884-121X
Print ISSN : 1343-9677
Sn-Ag-Bi-Cu系無鉛はんだの引け巣と合金組成
大類 研遠山 年男冨塚 健一
著者情報
ジャーナル フリー

2002 年 5 巻 6 号 p. 599-603

詳細
抄録

Correlation between composition and shrinkage cavity of Sn-Ag-Bi-Cu lead-free solder alloys was investigated. Incidence of surface cracks on solder fillets, caused by shrinkage cavity, was significantly influenced by Ag content of solder alloys (1.0-2.5wt%) ; for solder fillets with less than 2.0wt% of Ag content, surface cracks decreased in accordance with a reduction in Ag content. On the other hand, incidence of surface cracks was independent of Bi content of solder alloys (0-4.0wt%) . Compositional mapping analysis with EDX revealed that less Ag3Sn phases were formed for solder fillets with less Ag content, suggesting that the formation of the Ag3Sn/Sn eutectic network band triggers the formation of surface cracks, i.e., shrinkage cavity. Wettability of solder alloys with various Ag contents was also investigated. It was clarified that a decrease in Ag content leaded to degradation of solder wettability, indicating an increase in liquidus temperature of solder.

著者関連情報
© 一般社団法人エレクトロニクス実装学会
前の記事 次の記事
feedback
Top