Sn-9Zn-xAg钎料在Cu基材上润湿性能及界面组织的研究

Investigation on the Wettability and Interfacial Structure of Sn-9Zn-xAg Solders on Cu Substrate

研究了添加合金元素Ag对Sn9Zn无铅钎料显微组织、在铜基上的润湿性能及对钎料／铜界面组织的影响。研究结果表明：当Ag的含量（质量分数，下同）在0．1％～0．3％时，钎料中针状富zn相逐渐减少，当Ag的含量在0．5％～1％时，钎料中出现Ag—Zn化合物相；当Ag的含量为0．3％时，钎料具有最好的润湿性能，当Ag的含量为0．5％～1％时，钎料的润湿性能下降；Sn-9Zn／Cu的界面处形成平坦的Cu。Zn。化合物层，当Ag含量为0．3％时，在Cu5Zn8化合物层上出现节结状的AgZn3化合物相，随着Ag含量的提高，这种节结状的AgZn3化合物相逐渐聚集长大成扇贝状的化合物层。

The effect of Ag addition in Sn-9Zn solder on its microstrueture and wettability was investigated, and interfaeial structure of solder/Cu was also examined. Results show that, when the addition of Ag is lower than 0.3%, the needle-like Zn-rich phases decrease gradually. But when the content of Ag is between 0.5% and 1%, Ag-Zn intermetallic compounds appear in the solders. When the content of Ag is 0.3%, the solder presents the best wettability. When the content of Ag reaches 0. 5%- 1%, the wettability decreases. Intermetallic compound formed at the Sn-Zn/Cu interface is a planar layer （Cu5Zn8）. As for the Sn-Zn-0.3Ag/Cu interface, additional nodules （AgZn3） are visible beside the aforementioned planar layer. And the additional nodules grow up to a scalloped layer gradually as the content of Ag increases.